diff --git a/sdk/storage/azure-storage-blob/azure/storage/blob/_blob_client.py b/sdk/storage/azure-storage-blob/azure/storage/blob/_blob_client.py
index 957384e1c1d0..675b5a5e72c0 100644
--- a/sdk/storage/azure-storage-blob/azure/storage/blob/_blob_client.py
+++ b/sdk/storage/azure-storage-blob/azure/storage/blob/_blob_client.py
@@ -8,8 +8,8 @@
 from io import BytesIO
 from typing import (  # pylint: disable=unused-import
     Union, Optional, Any, IO, Iterable, AnyStr, Dict, List, Tuple,
-    TYPE_CHECKING
-)
+    TYPE_CHECKING,
+    TypeVar, Type)
 
 try:
     from urllib.parse import urlparse, quote, unquote
@@ -74,6 +74,8 @@
     'The require_encryption flag is set, but encryption is not supported'
     ' for this method.')
 
+ClassType = TypeVar("ClassType")
+
 
 class BlobClient(StorageAccountHostsMixin):  # pylint: disable=too-many-public-methods
     """A client to interact with a specific blob, although that blob may not yet exist.
@@ -202,7 +204,7 @@ def _encode_source_url(self, source_url):
 
     @classmethod
     def from_blob_url(cls, blob_url, credential=None, snapshot=None, **kwargs):
-        # type: (str, Optional[Any], Optional[Union[str, Dict[str, Any]]], Any) -> BlobClient
+        # type: (Type[ClassType], str, Optional[Any], Optional[Union[str, Dict[str, Any]]], Any) -> ClassType
         """Create BlobClient from a blob url. This doesn't support customized blob url with '/' in blob name.
 
         :param str blob_url:
@@ -272,13 +274,14 @@ def from_blob_url(cls, blob_url, credential=None, snapshot=None, **kwargs):
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             container_name,  # type: str
             blob_name,  # type: str
             snapshot=None,  # type: Optional[str]
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> BlobClient
+        ):  # type: (...) -> ClassType
         """Create BlobClient from a Connection String.
 
         :param str conn_str:
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 2b8a99a2fa9b..9dddb113ff72 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
@@ -8,8 +8,8 @@
 import warnings
 from typing import (  # pylint: disable=unused-import
     Union, Optional, Any, Iterable, Dict, List,
-    TYPE_CHECKING
-)
+    TYPE_CHECKING,
+    TypeVar)
 
 
 try:
@@ -52,6 +52,8 @@
         FilteredBlob
     )
 
+ClassType = TypeVar("ClassType")
+
 
 class BlobServiceClient(StorageAccountHostsMixin):
     """A client to interact with the Blob Service at the account level.
@@ -144,10 +146,11 @@ def _format_url(self, hostname):
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> BlobServiceClient
+        ):  # type: (...) -> ClassType
         """Create BlobServiceClient from a Connection String.
 
         :param str conn_str:
diff --git a/sdk/storage/azure-storage-blob/azure/storage/blob/_container_client.py b/sdk/storage/azure-storage-blob/azure/storage/blob/_container_client.py
index afa10add6feb..8b0a96ba55f7 100644
--- a/sdk/storage/azure-storage-blob/azure/storage/blob/_container_client.py
+++ b/sdk/storage/azure-storage-blob/azure/storage/blob/_container_client.py
@@ -8,8 +8,8 @@
 import functools
 from typing import (  # pylint: disable=unused-import
     Union, Optional, Any, Iterable, AnyStr, Dict, List, Tuple, IO, Iterator,
-    TYPE_CHECKING
-)
+    TYPE_CHECKING,
+    TypeVar)
 
 
 try:
@@ -69,6 +69,9 @@ def _get_blob_name(blob):
         return blob
 
 
+ClassType = TypeVar("ClassType")
+
+
 class ContainerClient(StorageAccountHostsMixin):    # pylint: disable=too-many-public-methods
     """A client to interact with a specific container, although that container
     may not yet exist.
@@ -170,7 +173,7 @@ def _format_url(self, hostname):
 
     @classmethod
     def from_container_url(cls, container_url, credential=None, **kwargs):
-        # type: (str, Optional[Any], Any) -> ContainerClient
+        # type: (Type[ClassType], str, Optional[Any], Any) -> ClassType
         """Create ContainerClient from a container url.
 
         :param str container_url:
@@ -213,11 +216,12 @@ def from_container_url(cls, container_url, credential=None, **kwargs):
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             container_name,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> ContainerClient
+        ):  # type: (...) -> ClassType
         """Create ContainerClient from a Connection String.
 
         :param str conn_str:
diff --git a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_directory_client.py b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_directory_client.py
index 042fa0551590..49aac0887889 100644
--- a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_directory_client.py
+++ b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_directory_client.py
@@ -3,7 +3,7 @@
 # Licensed under the MIT License. See License.txt in the project root for
 # license information.
 # --------------------------------------------------------------------------
-from typing import Any
+from typing import Any, TypeVar
 
 try:
     from urllib.parse import quote, unquote
@@ -16,6 +16,8 @@
 from ._models import DirectoryProperties, FileProperties
 from ._path_client import PathClient
 
+ClassType = TypeVar("ClassType")
+
 
 class DataLakeDirectoryClient(PathClient):
     """A client to interact with the DataLake directory, even if the directory may not yet exist.
@@ -67,12 +69,13 @@ def __init__(
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             file_system_name,  # type: str
             directory_name,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> DataLakeDirectoryClient
+        ):  # type: (...) -> ClassType
         """
         Create DataLakeDirectoryClient from a Connection String.
 
diff --git a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_file_client.py b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_file_client.py
index fe074b3a49db..a06c1348908b 100644
--- a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_file_client.py
+++ b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_file_client.py
@@ -4,7 +4,7 @@
 # license information.
 # --------------------------------------------------------------------------
 from io import BytesIO
-from typing import Any
+from typing import Any, TypeVar
 
 try:
     from urllib.parse import quote, unquote
@@ -27,6 +27,8 @@
 from ._deserialize import process_storage_error, deserialize_file_properties
 from ._models import FileProperties, DataLakeFileQueryError
 
+ClassType = TypeVar("ClassType")
+
 
 class DataLakeFileClient(PathClient):
     """A client to interact with the DataLake file, even if the file may not yet exist.
@@ -76,12 +78,13 @@ def __init__(
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             file_system_name,  # type: str
             file_path,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> DataLakeFileClient
+        ):  # type: (...) -> ClassType
         """
         Create DataLakeFileClient from a Connection String.
 
diff --git a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_service_client.py b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_service_client.py
index 776b98cda9d6..dfd5ca5b6e5d 100644
--- a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_service_client.py
+++ b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_data_lake_service_client.py
@@ -3,7 +3,7 @@
 # Licensed under the MIT License. See License.txt in the project root for
 # license information.
 # --------------------------------------------------------------------------
-from typing import Optional, Dict, Any
+from typing import Optional, Dict, Any, TypeVar
 
 try:
     from urllib.parse import urlparse
@@ -23,6 +23,8 @@
 from ._serialize import convert_dfs_url_to_blob_url, get_api_version
 from ._generated import AzureDataLakeStorageRESTAPI
 
+ClassType = TypeVar("ClassType")
+
 
 class DataLakeServiceClient(StorageAccountHostsMixin):
     """A client to interact with the DataLake Service at the account level.
@@ -120,10 +122,11 @@ def _format_url(self, hostname):
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> DataLakeServiceClient
+        ):  # type: (...) -> ClassType
         """
         Create DataLakeServiceClient from a Connection String.
 
diff --git a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_file_system_client.py b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_file_system_client.py
index b6f7c4c6299e..5026c96d2426 100644
--- a/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_file_system_client.py
+++ b/sdk/storage/azure-storage-file-datalake/azure/storage/filedatalake/_file_system_client.py
@@ -4,8 +4,7 @@
 # license information.
 # --------------------------------------------------------------------------
 import functools
-from typing import Optional, Any, Union, Iterator
-
+from typing import Optional, Any, Union, TypeVar, Iterator
 
 try:
     from urllib.parse import urlparse, quote, unquote
@@ -32,6 +31,9 @@
 from ._deserialize import deserialize_path_properties, process_storage_error, is_file_path
 
 
+ClassType = TypeVar("ClassType")
+
+
 class FileSystemClient(StorageAccountHostsMixin):
     """A client to interact with a specific file system, even if that file system
     may not yet exist.
@@ -137,11 +139,12 @@ def close(self):
 
     @classmethod
     def from_connection_string(
-            cls, conn_str,  # type: str
+            cls,  # type: Type[ClassType]
+            conn_str,  # type: str
             file_system_name,  # type: str
             credential=None,  # type: Optional[Any]
             **kwargs  # type: Any
-        ):  # type: (...) -> FileSystemClient
+        ):  # type: (...) -> ClassType
         """
         Create FileSystemClient from a Connection String.