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opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/_view_instrument_match.py

@@ -136,4 +136,8 @@ def collect(
                 )
                 if data_point is not None:
                     data_points.append(data_point)
+
+        # Returning here None instead of an empty list because the caller
+        # does not consume a sequence and to be consistent with the rest of
+        # collect methods that also return None.
         return data_points or None