Support Python 3.7

.github/workflows/python-package.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.8]
+        python-version: [3.7, 3.8]
 
     steps:
     - uses: actions/checkout@v2

README.md

@@ -35,7 +35,7 @@ python -m atcoder [your-source-code] -o [single-combined-code]
 
 ### For all users
 
-+ Python 3.8.2
++ Python 3.7.0+, 3.8.0+
 + pip
 
 ### For developer

README_ja.md

@@ -32,7 +32,7 @@ python -m atcoder [your-source-code] -o [single-combined-code]
 
 ### 利用者、開発者向け情報
 
-+ Python 3.8.2
++ Python 3.7.0+, 3.8.0+
 + pip
 
 ### 開発者向け情報

atcoder/__main__.py

@@ -33,10 +33,18 @@ def iter_child_nodes(
     if isinstance(node, ast.Import):
         for name in node.names:
             if re.match(r'^atcoder\.?', name.name):
-                import_info = ImportInfo(node.lineno, node.end_lineno)
+                if hasattr(node, 'end_lineno'):
+                    end_lineno = node.end_lineno
+                else:
+                    end_lineno = node.lineno
+                import_info = ImportInfo(node.lineno, end_lineno)
     elif isinstance(node, ast.ImportFrom):
         if re.match(r'^atcoder\.?', node.module):
-            import_info = ImportInfo(node.lineno, node.end_lineno, node.module)
+            if hasattr(node, 'end_lineno'):
+                end_lineno = node.end_lineno
+            else:
+                end_lineno = node.lineno
+            import_info = ImportInfo(node.lineno, end_lineno, node.module)
 
     for child in ast.iter_child_nodes(node):
         result += iter_child_nodes(child, import_info)