diff --git a/sdk/storage/azure-storage-blob/HISTORY.md b/sdk/storage/azure-storage-blob/HISTORY.md
index 19adb3fc1c4d..c1a63491eb3c 100644
--- a/sdk/storage/azure-storage-blob/HISTORY.md
+++ b/sdk/storage/azure-storage-blob/HISTORY.md
@@ -7,6 +7,9 @@
 - `set_container_access_policy` has required parameter `signed_identifiers`.
 - NoRetry policy has been removed. Use keyword argument `retry_total=0` for no retries. 
 
+**New features**
+
+- `ResourceTypes`, and `Services` now have method `from_string` which takes parameters as a string.
 
 ## Version 12.0.0b4:
 
@@ -44,6 +47,8 @@ changed include:
 - Add support for set_premium_page_blob_tier_blobs to ContainerClient (Python 3 only)
 - Added support to set rehydrate blob priority for Block Blob, including Set Standard Blob Tier/Copy Blob APIs
 - Added blob tier support for Block Blob, including Upload Blob/Commit Block List/Copy Blob APIs.
+- `AccountSasPermissions`, `BlobSasPermissions`, `ContainerSasPermissions` now have method `from_string` 
+which takes parameters as a string.
 
 **Fixes and improvements**
 - Downloading page blobs now take advantage of their sparseness.
diff --git a/sdk/storage/azure-storage-blob/azure/storage/blob/_shared/models.py b/sdk/storage/azure-storage-blob/azure/storage/blob/_shared/models.py
index c42edbc3745f..80c4d22a6b2f 100644
--- a/sdk/storage/azure-storage-blob/azure/storage/blob/_shared/models.py
+++ b/sdk/storage/azure-storage-blob/azure/storage/blob/_shared/models.py
@@ -225,16 +225,6 @@ class ResourceTypes(object):
     """
     Specifies the resource types that are accessible with the account SAS.
 
-    :cvar ResourceTypes ResourceTypes.CONTAINER:
-        Access to container-level APIs (e.g., Create/Delete Container,
-        Create/Delete Queue, Create/Delete Share,
-        List Blobs/Files and Directories)
-    :cvar ResourceTypes ResourceTypes.OBJECT:
-        Access to object-level APIs for blobs, queue messages, and
-        files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :cvar ResourceTypes ResourceTypes.SERVICE:
-        Access to service-level APIs (e.g., Get/Set Service Properties,
-        Get Service Stats, List Containers/Queues/Shares)
     :param bool service:
         Access to service-level APIs (e.g., Get/Set Service Properties,
         Get Service Stats, List Containers/Queues/Shares)
@@ -245,36 +235,28 @@ class ResourceTypes(object):
     :param bool object:
         Access to object-level APIs for blobs, queue messages, and
         files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :param str _str:
-        A string representing the resource types.
     """
 
-    SERVICE = None  # type: ResourceTypes
-    CONTAINER = None  # type: ResourceTypes
-    OBJECT = None  # type: ResourceTypes
-
-    def __init__(self, service=False, container=False, object=False, _str=None):  # pylint: disable=redefined-builtin
-        if not _str:
-            _str = ''
-        self.service = service or ('s' in _str)
-        self.container = container or ('c' in _str)
-        self.object = object or ('o' in _str)
-
-    def __or__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('s' if self.service else '') +
+    def __init__(self, service=False, container=False, object=False):  # pylint: disable=redefined-builtin
+        self.service = service
+        self.container = container
+        self.object = object
+        self._str = (('s' if self.service else '') +
                 ('c' if self.container else '') +
                 ('o' if self.object else ''))
 
+    def __str__(self):
+        return self._str
+
+    @classmethod
+    def from_string(cls, string):
+        res_service = 's' in string
+        res_container = 'c' in string
+        res_object = 'o' in string
 
-ResourceTypes.SERVICE = ResourceTypes(service=True)
-ResourceTypes.CONTAINER = ResourceTypes(container=True)
-ResourceTypes.OBJECT = ResourceTypes(object=True)
+        parsed = cls(res_service, res_container, res_object)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 
 class AccountSasPermissions(object):
@@ -348,46 +330,34 @@ def from_string(cls, permission):
 class Services(object):
     """Specifies the services accessible with the account SAS.
 
-    :cvar Services Services.BLOB: The blob service.
-    :cvar Services Services.FILE: The file service
-    :cvar Services Services.QUEUE: The queue service.
     :param bool blob:
         Access for the `~azure.storage.blob.blob_service_client.BlobServiceClient`
     :param bool queue:
         Access for the `~azure.storage.queue.queue_service_client.QueueServiceClient`
     :param bool file:
         Access for the `~azure.storage.file.file_service_client.FileServiceClient`
-    :param str _str:
-        A string representing the services.
     """
 
-    BLOB = None # type: Services
-    QUEUE = None # type: Services
-    FILE = None # type: Services
-
-    def __init__(self, blob=False, queue=False, file=False, _str=None):
-        if not _str:
-            _str = ''
-        self.blob = blob or ('b' in _str)
-        self.queue = queue or ('q' in _str)
-        self.file = file or ('f' in _str)
-
-    def __or__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('b' if self.blob else '') +
+    def __init__(self, blob=False, queue=False, file=False):
+        self.blob = blob
+        self.queue = queue
+        self.file = file
+        self._str = (('b' if self.blob else '') +
                 ('q' if self.queue else '') +
                 ('f' if self.file else ''))
 
+    def __str__(self):
+        return self._str
 
-Services.BLOB = Services(blob=True)
-Services.QUEUE = Services(queue=True)
-Services.FILE = Services(file=True)
+    @classmethod
+    def from_string(cls, string):
+        res_blob = 'b' in string
+        res_queue = 'q' in string
+        res_file = 'f' in string
 
+        parsed = cls(res_blob, res_queue, res_file)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 class UserDelegationKey(object):
     """
diff --git a/sdk/storage/azure-storage-blob/azure/storage/blob/blob_service_client.py b/sdk/storage/azure-storage-blob/azure/storage/blob/blob_service_client.py
index dff7cbf0dfa0..7293401b7baa 100644
--- a/sdk/storage/azure-storage-blob/azure/storage/blob/blob_service_client.py
+++ b/sdk/storage/azure-storage-blob/azure/storage/blob/blob_service_client.py
@@ -221,7 +221,7 @@ def generate_shared_access_signature(
 
         sas = SharedAccessSignature(self.credential.account_name, self.credential.account_key)
         return sas.generate_account(
-            services=Services.BLOB,
+            services=Services(blob=True),
             resource_types=resource_types,
             permission=permission,
             expiry=expiry,
diff --git a/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication.py b/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication.py
index 930fd8c666a3..780c7660823b 100644
--- a/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication.py
+++ b/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication.py
@@ -118,7 +118,7 @@ def test_auth_shared_access_signature(self):
         from azure.storage.blob import ResourceTypes, AccountSasPermissions
 
         sas_token = blob_service_client.generate_shared_access_signature(
-            resource_types=ResourceTypes.OBJECT,
+            resource_types=ResourceTypes(object=True),
             permission=AccountSasPermissions(read=True),
             expiry=datetime.utcnow() + timedelta(hours=1)
         )
diff --git a/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication_async.py b/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication_async.py
index f9783f26ad36..817a75882e76 100644
--- a/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication_async.py
+++ b/sdk/storage/azure-storage-blob/tests/test_blob_samples_authentication_async.py
@@ -143,7 +143,7 @@ async def _test_auth_shared_access_signature_async(self):
         from azure.storage.blob import ResourceTypes, AccountSasPermissions
 
         sas_token = blob_service_client.generate_shared_access_signature(
-            resource_types=ResourceTypes.OBJECT,
+            resource_types=ResourceTypes(object=True),
             permission=AccountSasPermissions(read=True),
             expiry=datetime.utcnow() + timedelta(hours=1)
         )
diff --git a/sdk/storage/azure-storage-file/HISTORY.md b/sdk/storage/azure-storage-file/HISTORY.md
index c5ed88ae81e1..90469ea1e899 100644
--- a/sdk/storage/azure-storage-file/HISTORY.md
+++ b/sdk/storage/azure-storage-file/HISTORY.md
@@ -6,8 +6,11 @@
 
 - `file_permission_key` parameter has been renamed to `permission_key`
 - `set_share_access_policy` has required parameter `signed_identifiers`.
-- NoRetry policy has been removed. Use keyword argument `retry_total=0` for no retries. 
+- NoRetry policy has been removed. Use keyword argument `retry_total=0` for no retries.
 
+**New features**
+
+- `ResourceTypes`, `NTFSAttributes`, and `Services` now have method `from_string` which takes parameters as a string.
 
 ## Version 12.0.0b4:
 
@@ -20,6 +23,11 @@
   - `__add__` and `__or__` methods are removed.
 - `max_connections` is now renamed to `max_concurrency`.
 
+**New features**
+
+- `AccountSasPermissions`, `FileSasPermissions`, `ShareSasPermissions` now have method `from_string` which 
+takes parameters as a string.
+
 ## Version 12.0.0b3:
 
 **New features**
diff --git a/sdk/storage/azure-storage-file/azure/storage/file/_shared/models.py b/sdk/storage/azure-storage-file/azure/storage/file/_shared/models.py
index 3234c72b534f..943842ced4c2 100644
--- a/sdk/storage/azure-storage-file/azure/storage/file/_shared/models.py
+++ b/sdk/storage/azure-storage-file/azure/storage/file/_shared/models.py
@@ -225,16 +225,6 @@ class ResourceTypes(object):
     """
     Specifies the resource types that are accessible with the account SAS.
 
-    :cvar ResourceTypes ResourceTypes.CONTAINER:
-        Access to container-level APIs (e.g., Create/Delete Container,
-        Create/Delete Queue, Create/Delete Share,
-        List Blobs/Files and Directories)
-    :cvar ResourceTypes ResourceTypes.OBJECT:
-        Access to object-level APIs for blobs, queue messages, and
-        files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :cvar ResourceTypes ResourceTypes.SERVICE:
-        Access to service-level APIs (e.g., Get/Set Service Properties,
-        Get Service Stats, List Containers/Queues/Shares)
     :param bool service:
         Access to service-level APIs (e.g., Get/Set Service Properties,
         Get Service Stats, List Containers/Queues/Shares)
@@ -245,36 +235,28 @@ class ResourceTypes(object):
     :param bool object:
         Access to object-level APIs for blobs, queue messages, and
         files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :param str _str:
-        A string representing the resource types.
     """
 
-    SERVICE = None  # type: ResourceTypes
-    CONTAINER = None  # type: ResourceTypes
-    OBJECT = None  # type: ResourceTypes
-
-    def __init__(self, service=False, container=False, object=False, _str=None):  # pylint: disable=redefined-builtin
-        if not _str:
-            _str = ''
-        self.service = service or ('s' in _str)
-        self.container = container or ('c' in _str)
-        self.object = object or ('o' in _str)
-
-    def __or__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('s' if self.service else '') +
+    def __init__(self, service=False, container=False, object=False):  # pylint: disable=redefined-builtin
+        self.service = service
+        self.container = container
+        self.object = object
+        self._str = (('s' if self.service else '') +
                 ('c' if self.container else '') +
                 ('o' if self.object else ''))
 
+    def __str__(self):
+        return self._str
+
+    @classmethod
+    def from_string(cls, string):
+        res_service = 's' in string
+        res_container = 'c' in string
+        res_object = 'o' in string
 
-ResourceTypes.SERVICE = ResourceTypes(service=True)
-ResourceTypes.CONTAINER = ResourceTypes(container=True)
-ResourceTypes.OBJECT = ResourceTypes(object=True)
+        parsed = cls(res_service, res_container, res_object)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 
 class AccountSasPermissions(object):
@@ -285,6 +267,7 @@ class AccountSasPermissions(object):
     specific resource (resource-specific). Another is to grant access to the
     entire service for a specific account and allow certain operations based on
     perms found here.
+
     :param bool read:
         Valid for all signed resources types (Service, Container, and Object).
         Permits read permissions to the specified resource type.
@@ -346,45 +329,34 @@ def from_string(cls, permission):
 class Services(object):
     """Specifies the services accessible with the account SAS.
 
-    :cvar Services Services.BLOB: The blob service.
-    :cvar Services Services.FILE: The file service
-    :cvar Services Services.QUEUE: The queue service.
     :param bool blob:
         Access for the `~azure.storage.blob.blob_service_client.BlobServiceClient`
     :param bool queue:
         Access for the `~azure.storage.queue.queue_service_client.QueueServiceClient`
     :param bool file:
         Access for the `~azure.storage.file.file_service_client.FileServiceClient`
-    :param str _str:
-        A string representing the services.
     """
 
-    BLOB = None # type: Services
-    QUEUE = None # type: Services
-    FILE = None # type: Services
-
-    def __init__(self, blob=False, queue=False, file=False, _str=None):
-        if not _str:
-            _str = ''
-        self.blob = blob or ('b' in _str)
-        self.queue = queue or ('q' in _str)
-        self.file = file or ('f' in _str)
-
-    def __or__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('b' if self.blob else '') +
+    def __init__(self, blob=False, queue=False, file=False):
+        self.blob = blob
+        self.queue = queue
+        self.file = file
+        self._str = (('b' if self.blob else '') +
                 ('q' if self.queue else '') +
                 ('f' if self.file else ''))
 
+    def __str__(self):
+        return self._str
 
-Services.BLOB = Services(blob=True)
-Services.QUEUE = Services(queue=True)
-Services.FILE = Services(file=True)
+    @classmethod
+    def from_string(cls, string):
+        res_blob = 'b' in string
+        res_queue = 'q' in string
+        res_file = 'f' in string
+
+        parsed = cls(res_blob, res_queue, res_file)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 
 class UserDelegationKey(object):
diff --git a/sdk/storage/azure-storage-file/azure/storage/file/file_service_client.py b/sdk/storage/azure-storage-file/azure/storage/file/file_service_client.py
index f2d6ee41666a..434de64c3654 100644
--- a/sdk/storage/azure-storage-file/azure/storage/file/file_service_client.py
+++ b/sdk/storage/azure-storage-file/azure/storage/file/file_service_client.py
@@ -198,7 +198,7 @@ def generate_shared_access_signature(
 
         sas = SharedAccessSignature(self.credential.account_name, self.credential.account_key)
         return sas.generate_account(
-            services=Services.FILE,
+            services=Services(file=True),
             resource_types=resource_types,
             permission=permission,
             expiry=expiry,
diff --git a/sdk/storage/azure-storage-file/azure/storage/file/models.py b/sdk/storage/azure-storage-file/azure/storage/file/models.py
index 67aa5967a0e4..de65f213a916 100644
--- a/sdk/storage/azure-storage-file/azure/storage/file/models.py
+++ b/sdk/storage/azure-storage-file/azure/storage/file/models.py
@@ -742,28 +742,19 @@ class NTFSAttributes(object):
         Enable/disable 'NoScrubData' attribute for DIRECTORY or FILE
     """
     def __init__(self, read_only=False, hidden=False, system=False, none=False, directory=False, archive=False,
-                 temporary=False, offline=False, not_content_indexed=False, no_scrub_data=False, _str=None):
-        if not _str:
-            _str = ''
-        self.read_only = read_only or ('ReadOnly' in _str)
-        self.hidden = hidden or ('Hidden' in _str)
-        self.system = system or ('System' in _str)
-        self.none = none or ('None' in _str)
-        self.directory = directory or ('Directory' in _str)
-        self.archive = archive or ('Archive' in _str)
-        self.temporary = temporary or ('Temporary' in _str)
-        self.offline = offline or ('Offline' in _str)
-        self.not_content_indexed = not_content_indexed or ('NotContentIndexed' in _str)
-        self.no_scrub_data = no_scrub_data or ('NoScrubData' in _str)
-
-    def __or__(self, other):
-        return NTFSAttributes(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return NTFSAttributes(_str=str(self) + str(other))
-
-    def __str__(self):
-        concatenated_params = (('ReadOnly|' if self.read_only else '') +
+                 temporary=False, offline=False, not_content_indexed=False, no_scrub_data=False):
+
+        self.read_only = read_only
+        self.hidden = hidden
+        self.system = system
+        self.none = none
+        self.directory = directory
+        self.archive = archive
+        self.temporary = temporary
+        self.offline = offline
+        self.not_content_indexed = not_content_indexed
+        self.no_scrub_data = no_scrub_data
+        self._str = (('ReadOnly|' if self.read_only else '') +
                                ('Hidden|' if self.hidden else '') +
                                ('System|' if self.system else '') +
                                ('None|' if self.none else '') +
@@ -774,16 +765,24 @@ def __str__(self):
                                ('NotContentIndexed|' if self.not_content_indexed else '') +
                                ('NoScrubData|' if self.no_scrub_data else ''))
 
+    def __str__(self):
+        concatenated_params = self._str
         return concatenated_params.strip('|')
 
-
-NTFSAttributes.READ_ONLY = NTFSAttributes(read_only=True)
-NTFSAttributes.HIDDEN = NTFSAttributes(hidden=True)
-NTFSAttributes.SYSTEM = NTFSAttributes(system=True)
-NTFSAttributes.NONE = NTFSAttributes(none=True)
-NTFSAttributes.DIRECTORY = NTFSAttributes(directory=True)
-NTFSAttributes.ARCHIVE = NTFSAttributes(archive=True)
-NTFSAttributes.TEMPORARY = NTFSAttributes(temporary=True)
-NTFSAttributes.OFFLINE = NTFSAttributes(offline=True)
-NTFSAttributes.NOT_CONTENT_INDEXED = NTFSAttributes(not_content_indexed=True)
-NTFSAttributes.NO_SCRUB_DATA = NTFSAttributes(no_scrub_data=True)
+    @classmethod
+    def from_string(cls, string):
+        read_only = "ReadOnly" in string
+        hidden = "Hidden" in string
+        system = "System" in string
+        none = "None" in string
+        directory = "Directory" in string
+        archive = "Archive" in string
+        temporary = "Temporary" in string
+        offline = "Offline" in string
+        not_content_indexed = "NotContentIndexed" in string
+        no_scrub_data = "NoScrubData" in string
+
+        parsed = cls(read_only, hidden, system, none, directory, archive, temporary, offline, not_content_indexed,
+                     no_scrub_data)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
diff --git a/sdk/storage/azure-storage-file/tests/test_file.py b/sdk/storage/azure-storage-file/tests/test_file.py
index 97d677dbd3d3..47441500d4c5 100644
--- a/sdk/storage/azure-storage-file/tests/test_file.py
+++ b/sdk/storage/azure-storage-file/tests/test_file.py
@@ -1456,7 +1456,7 @@ def test_account_sas(self):
         # Arrange
         file_client = self._create_file()
         token = self.fsc.generate_shared_access_signature(
-            ResourceTypes.OBJECT,
+            ResourceTypes(object=True),
             AccountSasPermissions(read=True),
             datetime.utcnow() + timedelta(hours=1),
         )
diff --git a/sdk/storage/azure-storage-file/tests/test_file_async.py b/sdk/storage/azure-storage-file/tests/test_file_async.py
index 68a29bd49f03..f866d92fc012 100644
--- a/sdk/storage/azure-storage-file/tests/test_file_async.py
+++ b/sdk/storage/azure-storage-file/tests/test_file_async.py
@@ -1797,7 +1797,7 @@ async def _test_account_sas_async(self):
         # Arrange
         file_client = await self._create_file()
         token = self.fsc.generate_shared_access_signature(
-            ResourceTypes.OBJECT,
+            ResourceTypes(object=True),
             AccountSasPermissions(read=True),
             datetime.utcnow() + timedelta(hours=1),
         )
diff --git a/sdk/storage/azure-storage-queue/HISTORY.md b/sdk/storage/azure-storage-queue/HISTORY.md
index ff0243385bdf..9d9ead72bb17 100644
--- a/sdk/storage/azure-storage-queue/HISTORY.md
+++ b/sdk/storage/azure-storage-queue/HISTORY.md
@@ -5,7 +5,11 @@
 **Breaking changes**
 
 - `set_queue_access_policy` has required parameter `signed_identifiers`.
-- NoRetry policy has been removed. Use keyword argument `retry_total=0` for no retries. 
+- NoRetry policy has been removed. Use keyword argument `retry_total=0` for no retries.
+
+ **New features**
+ 
+- `ResourceTypes`, and `Services` now have method `from_string` which takes parameters as a string.
 
 
 ## Version 12.0.0b4:
@@ -19,6 +23,10 @@
   - `__add__` and `__or__` methods are removed.
 - `max_connections` is now renamed to `max_concurrency`.
 
+**New features**
+
+- `AccountSasPermissions`, `QueueSasPermissions` now have method `from_string` which takes parameters as a string.
+
 ## Version 12.0.0b3:
 
 **Dependency updates**
diff --git a/sdk/storage/azure-storage-queue/azure/storage/queue/_shared/models.py b/sdk/storage/azure-storage-queue/azure/storage/queue/_shared/models.py
index 0fd6d4de786c..b8078927e0de 100644
--- a/sdk/storage/azure-storage-queue/azure/storage/queue/_shared/models.py
+++ b/sdk/storage/azure-storage-queue/azure/storage/queue/_shared/models.py
@@ -225,16 +225,6 @@ class ResourceTypes(object):
     """
     Specifies the resource types that are accessible with the account SAS.
 
-    :cvar ResourceTypes ResourceTypes.CONTAINER:
-        Access to container-level APIs (e.g., Create/Delete Container,
-        Create/Delete Queue, Create/Delete Share,
-        List Blobs/Files and Directories)
-    :cvar ResourceTypes ResourceTypes.OBJECT:
-        Access to object-level APIs for blobs, queue messages, and
-        files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :cvar ResourceTypes ResourceTypes.SERVICE:
-        Access to service-level APIs (e.g., Get/Set Service Properties,
-        Get Service Stats, List Containers/Queues/Shares)
     :param bool service:
         Access to service-level APIs (e.g., Get/Set Service Properties,
         Get Service Stats, List Containers/Queues/Shares)
@@ -245,36 +235,28 @@ class ResourceTypes(object):
     :param bool object:
         Access to object-level APIs for blobs, queue messages, and
         files(e.g. Put Blob, Query Entity, Get Messages, Create File, etc.)
-    :param str _str:
-        A string representing the resource types.
     """
 
-    SERVICE = None  # type: ResourceTypes
-    CONTAINER = None  # type: ResourceTypes
-    OBJECT = None  # type: ResourceTypes
-
-    def __init__(self, service=False, container=False, object=False, _str=None):  # pylint: disable=redefined-builtin
-        if not _str:
-            _str = ''
-        self.service = service or ('s' in _str)
-        self.container = container or ('c' in _str)
-        self.object = object or ('o' in _str)
-
-    def __or__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return ResourceTypes(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('s' if self.service else '') +
+    def __init__(self, service=False, container=False, object=False):  # pylint: disable=redefined-builtin
+        self.service = service
+        self.container = container
+        self.object = object
+        self._str = (('s' if self.service else '') +
                 ('c' if self.container else '') +
                 ('o' if self.object else ''))
 
+    def __str__(self):
+        return self._str
 
-ResourceTypes.SERVICE = ResourceTypes(service=True)
-ResourceTypes.CONTAINER = ResourceTypes(container=True)
-ResourceTypes.OBJECT = ResourceTypes(object=True)
+    @classmethod
+    def from_string(cls, string):
+        res_service = 's' in string
+        res_container = 'c' in string
+        res_object = 'o' in string
+
+        parsed = cls(res_service, res_container, res_object)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 
 class AccountSasPermissions(object):
@@ -347,45 +329,34 @@ def from_string(cls, permission):
 class Services(object):
     """Specifies the services accessible with the account SAS.
 
-    :cvar Services Services.BLOB: The blob service.
-    :cvar Services Services.FILE: The file service
-    :cvar Services Services.QUEUE: The queue service.
     :param bool blob:
         Access for the `~azure.storage.blob.blob_service_client.BlobServiceClient`
     :param bool queue:
         Access for the `~azure.storage.queue.queue_service_client.QueueServiceClient`
     :param bool file:
         Access for the `~azure.storage.file.file_service_client.FileServiceClient`
-    :param str _str:
-        A string representing the services.
     """
 
-    BLOB = None # type: Services
-    QUEUE = None # type: Services
-    FILE = None # type: Services
-
-    def __init__(self, blob=False, queue=False, file=False, _str=None):
-        if not _str:
-            _str = ''
-        self.blob = blob or ('b' in _str)
-        self.queue = queue or ('q' in _str)
-        self.file = file or ('f' in _str)
-
-    def __or__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __add__(self, other):
-        return Services(_str=str(self) + str(other))
-
-    def __str__(self):
-        return (('b' if self.blob else '') +
+    def __init__(self, blob=False, queue=False, file=False):
+        self.blob = blob
+        self.queue = queue
+        self.file = file
+        self._str = (('b' if self.blob else '') +
                 ('q' if self.queue else '') +
                 ('f' if self.file else ''))
 
+    def __str__(self):
+        return self._str
+
+    @classmethod
+    def from_string(cls, string):
+        res_blob = 'b' in string
+        res_queue = 'q' in string
+        res_file = 'f' in string
 
-Services.BLOB = Services(blob=True)
-Services.QUEUE = Services(queue=True)
-Services.FILE = Services(file=True)
+        parsed = cls(res_blob, res_queue, res_file)
+        parsed._str = string  # pylint: disable = protected-access
+        return parsed
 
 
 class UserDelegationKey(object):
diff --git a/sdk/storage/azure-storage-queue/azure/storage/queue/queue_service_client.py b/sdk/storage/azure-storage-queue/azure/storage/queue/queue_service_client.py
index 7c04e38d4813..edd0c4f0ed33 100644
--- a/sdk/storage/azure-storage-queue/azure/storage/queue/queue_service_client.py
+++ b/sdk/storage/azure-storage-queue/azure/storage/queue/queue_service_client.py
@@ -198,7 +198,7 @@ def generate_shared_access_signature(
 
         sas = SharedAccessSignature(self.credential.account_name, self.credential.account_key)
         return sas.generate_account(
-            services=Services.QUEUE,
+            services=Services(queue=True),
             resource_types=resource_types,
             permission=permission,
             expiry=expiry,
diff --git a/sdk/storage/azure-storage-queue/tests/recordings/test_queue.test_account_sas.yaml b/sdk/storage/azure-storage-queue/tests/recordings/test_queue.test_account_sas.yaml
index 78d0219d19e0..82ff167df112 100644
--- a/sdk/storage/azure-storage-queue/tests/recordings/test_queue.test_account_sas.yaml
+++ b/sdk/storage/azure-storage-queue/tests/recordings/test_queue.test_account_sas.yaml
@@ -11,11 +11,9 @@ interactions:
       Content-Length:
       - '0'
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
-      content-type:
-      - application/xml; charset=utf-8
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:52:03 GMT
+      - Mon, 14 Oct 2019 17:42:19 GMT
       x-ms-version:
       - '2018-03-28'
     method: PUT
@@ -27,7 +25,7 @@ interactions:
       content-length:
       - '0'
       date:
-      - Fri, 06 Sep 2019 21:52:02 GMT
+      - Mon, 14 Oct 2019 17:42:15 GMT
       server:
       - Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       x-ms-version:
@@ -51,24 +49,24 @@ interactions:
       Content-Type:
       - application/xml; charset=utf-8
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:52:04 GMT
+      - Mon, 14 Oct 2019 17:42:20 GMT
       x-ms-version:
       - '2018-03-28'
     method: POST
     uri: https://pyacrstorage9c250b25.queue.core.windows.net/pythonqueue9c250b25/messages
   response:
     body:
-      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>b4d0220c-ce49-4953-86fd-871e34eb269f</MessageId><InsertionTime>Fri,
-        06 Sep 2019 21:52:02 GMT</InsertionTime><ExpirationTime>Fri, 13 Sep 2019 21:52:02
-        GMT</ExpirationTime><PopReceipt>AgAAAAMAAAAAAAAAZasDUf1k1QE=</PopReceipt><TimeNextVisible>Fri,
-        06 Sep 2019 21:52:02 GMT</TimeNextVisible></QueueMessage></QueueMessagesList>"
+      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>2ed39c4e-3a6a-4328-b26e-3d47ef45067a</MessageId><InsertionTime>Mon,
+        14 Oct 2019 17:42:16 GMT</InsertionTime><ExpirationTime>Mon, 21 Oct 2019 17:42:16
+        GMT</ExpirationTime><PopReceipt>AgAAAAMAAAAAAAAA1PYYuLaC1QE=</PopReceipt><TimeNextVisible>Mon,
+        14 Oct 2019 17:42:16 GMT</TimeNextVisible></QueueMessage></QueueMessagesList>"
     headers:
       content-type:
       - application/xml
       date:
-      - Fri, 06 Sep 2019 21:52:02 GMT
+      - Mon, 14 Oct 2019 17:42:16 GMT
       server:
       - Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       transfer-encoding:
@@ -88,17 +86,17 @@ interactions:
       Connection:
       - keep-alive
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:52:04 GMT
+      - Mon, 14 Oct 2019 17:42:20 GMT
       x-ms-version:
       - '2018-03-28'
     method: GET
-    uri: https://pyacrstorage9c250b25.queue.core.windows.net/pythonqueue9c250b25/messages?peekonly=true&st=2019-09-06T21%3A47%3A04Z&se=2019-09-06T22%3A52%3A04Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=SpqwtmOiwSKHBHaK2lrd5QSOc3KluM8DYlG2iZn6YE0%3D
+    uri: https://pyacrstorage9c250b25.queue.core.windows.net/pythonqueue9c250b25/messages?peekonly=true&st=2019-10-14T17%3A37%3A20Z&se=2019-10-14T18%3A42%3A20Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=KlW5dNogfEs3vFfAVtYWPKqJrAIF2GerVf8APb/Zf5I%3D
   response:
     body:
-      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>b4d0220c-ce49-4953-86fd-871e34eb269f</MessageId><InsertionTime>Fri,
-        06 Sep 2019 21:52:02 GMT</InsertionTime><ExpirationTime>Fri, 13 Sep 2019 21:52:02
+      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>2ed39c4e-3a6a-4328-b26e-3d47ef45067a</MessageId><InsertionTime>Mon,
+        14 Oct 2019 17:42:16 GMT</InsertionTime><ExpirationTime>Mon, 21 Oct 2019 17:42:16
         GMT</ExpirationTime><DequeueCount>0</DequeueCount><MessageText>message1</MessageText></QueueMessage></QueueMessagesList>"
     headers:
       cache-control:
@@ -106,7 +104,7 @@ interactions:
       content-type:
       - application/xml
       date:
-      - Fri, 06 Sep 2019 21:52:02 GMT
+      - Mon, 14 Oct 2019 17:42:16 GMT
       server:
       - Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       transfer-encoding:
diff --git a/sdk/storage/azure-storage-queue/tests/recordings/test_queue_async.test_account_sas.yaml b/sdk/storage/azure-storage-queue/tests/recordings/test_queue_async.test_account_sas.yaml
index 4fe8f57a2aa1..19ad305a52f8 100644
--- a/sdk/storage/azure-storage-queue/tests/recordings/test_queue_async.test_account_sas.yaml
+++ b/sdk/storage/azure-storage-queue/tests/recordings/test_queue_async.test_account_sas.yaml
@@ -3,11 +3,9 @@ interactions:
     body: null
     headers:
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
-      content-type:
-      - application/xml; charset=utf-8
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:53:39 GMT
+      - Mon, 14 Oct 2019 17:44:45 GMT
       x-ms-version:
       - '2018-03-28'
     method: PUT
@@ -17,7 +15,7 @@ interactions:
       string: ''
     headers:
       content-length: '0'
-      date: Fri, 06 Sep 2019 21:53:37 GMT
+      date: Mon, 14 Oct 2019 17:44:40 GMT
       server: Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       x-ms-version: '2018-03-28'
     status:
@@ -43,22 +41,22 @@ interactions:
       Content-Type:
       - application/xml; charset=utf-8
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:53:39 GMT
+      - Mon, 14 Oct 2019 17:44:45 GMT
       x-ms-version:
       - '2018-03-28'
     method: POST
     uri: https://pyacrstoragee8a50da2.queue.core.windows.net/pythonqueuee8a50da2/messages
   response:
     body:
-      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>fe3f5187-bf2b-4aac-9a72-0aba99faaa04</MessageId><InsertionTime>Fri,
-        06 Sep 2019 21:53:38 GMT</InsertionTime><ExpirationTime>Fri, 13 Sep 2019 21:53:38
-        GMT</ExpirationTime><PopReceipt>AgAAAAMAAAAAAAAAnlnxif1k1QE=</PopReceipt><TimeNextVisible>Fri,
-        06 Sep 2019 21:53:38 GMT</TimeNextVisible></QueueMessage></QueueMessagesList>"
+      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>bc87b9aa-0be1-41f8-abc0-9be61c68e3dd</MessageId><InsertionTime>Mon,
+        14 Oct 2019 17:44:41 GMT</InsertionTime><ExpirationTime>Mon, 21 Oct 2019 17:44:41
+        GMT</ExpirationTime><PopReceipt>AgAAAAMAAAAAAAAA2E2XDreC1QE=</PopReceipt><TimeNextVisible>Mon,
+        14 Oct 2019 17:44:41 GMT</TimeNextVisible></QueueMessage></QueueMessagesList>"
     headers:
       content-type: application/xml
-      date: Fri, 06 Sep 2019 21:53:37 GMT
+      date: Mon, 14 Oct 2019 17:44:40 GMT
       server: Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       transfer-encoding: chunked
       x-ms-version: '2018-03-28'
@@ -79,22 +77,22 @@ interactions:
       Accept:
       - application/xml
       User-Agent:
-      - azsdk-python-storage-queue/12.0.0b2 Python/3.7.3 (Windows-10-10.0.17763-SP0)
+      - azsdk-python-storage-queue/12.0.0b4 Python/3.7.3 (Windows-10-10.0.18362-SP0)
       x-ms-date:
-      - Fri, 06 Sep 2019 21:53:39 GMT
+      - Mon, 14 Oct 2019 17:44:45 GMT
       x-ms-version:
       - '2018-03-28'
     method: GET
-    uri: https://pyacrstoragee8a50da2.queue.core.windows.net/pythonqueuee8a50da2/messages?peekonly=true&st=2019-09-06T21:48:39Z&se=2019-09-06T22:53:39Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=y8ZamgWfnbV2cUmmOOoFvuy51HcnBXg4Ad%2Bl3u2VrFE%3D
+    uri: https://pyacrstoragee8a50da2.queue.core.windows.net/pythonqueuee8a50da2/messages?peekonly=true&st=2019-10-14T17:39:45Z&se=2019-10-14T18:44:45Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=bjMPAcJl2ocuk6f%2B%2B65rR8Dd6f9c5QnRuS0ELCJVwuo%3D
   response:
     body:
-      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>fe3f5187-bf2b-4aac-9a72-0aba99faaa04</MessageId><InsertionTime>Fri,
-        06 Sep 2019 21:53:38 GMT</InsertionTime><ExpirationTime>Fri, 13 Sep 2019 21:53:38
+      string: "\uFEFF<?xml version=\"1.0\" encoding=\"utf-8\"?><QueueMessagesList><QueueMessage><MessageId>bc87b9aa-0be1-41f8-abc0-9be61c68e3dd</MessageId><InsertionTime>Mon,
+        14 Oct 2019 17:44:41 GMT</InsertionTime><ExpirationTime>Mon, 21 Oct 2019 17:44:41
         GMT</ExpirationTime><DequeueCount>0</DequeueCount><MessageText>message1</MessageText></QueueMessage></QueueMessagesList>"
     headers:
       cache-control: no-cache
       content-type: application/xml
-      date: Fri, 06 Sep 2019 21:53:37 GMT
+      date: Mon, 14 Oct 2019 17:44:40 GMT
       server: Windows-Azure-Queue/1.0 Microsoft-HTTPAPI/2.0
       transfer-encoding: chunked
       x-ms-version: '2018-03-28'
@@ -107,6 +105,6 @@ interactions:
         - https
         - pyacrstoragee8a50da2.queue.core.windows.net
         - /pythonqueuee8a50da2/messages
-        - peekonly=true&st=2019-09-06T21:48:39Z&se=2019-09-06T22:53:39Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=y8ZamgWfnbV2cUmmOOoFvuy51HcnBXg4Ad%2Bl3u2VrFE%3D
+        - peekonly=true&st=2019-10-14T17:39:45Z&se=2019-10-14T18:44:45Z&sp=r&sv=2018-03-28&ss=q&srt=o&sig=bjMPAcJl2ocuk6f%2B%2B65rR8Dd6f9c5QnRuS0ELCJVwuo%3D
         - ''
 version: 1
diff --git a/sdk/storage/azure-storage-queue/tests/test_queue.py b/sdk/storage/azure-storage-queue/tests/test_queue.py
index 54f68f1fd929..c1a1e40b15e0 100644
--- a/sdk/storage/azure-storage-queue/tests/test_queue.py
+++ b/sdk/storage/azure-storage-queue/tests/test_queue.py
@@ -542,7 +542,7 @@ def test_account_sas(self, resource_group, location, storage_account, storage_ac
         queue_client.create_queue()
         queue_client.enqueue_message(u'message1')
         token = qsc.generate_shared_access_signature(
-            ResourceTypes.OBJECT,
+            ResourceTypes(object=True),
             AccountSasPermissions(read=True),
             datetime.utcnow() + timedelta(hours=1),
             datetime.utcnow() - timedelta(minutes=5)
diff --git a/sdk/storage/azure-storage-queue/tests/test_queue_async.py b/sdk/storage/azure-storage-queue/tests/test_queue_async.py
index f09ff148da2c..a287e3dd9a91 100644
--- a/sdk/storage/azure-storage-queue/tests/test_queue_async.py
+++ b/sdk/storage/azure-storage-queue/tests/test_queue_async.py
@@ -584,7 +584,7 @@ async def test_account_sas(self, resource_group, location, storage_account, stor
         queue_client = await self._create_queue(qsc)
         await queue_client.enqueue_message(u'message1')
         token = qsc.generate_shared_access_signature(
-            ResourceTypes.OBJECT,
+            ResourceTypes(object=True),
             AccountSasPermissions(read=True),
             datetime.utcnow() + timedelta(hours=1),
             datetime.utcnow() - timedelta(minutes=5)