code: def get_blob(
          self, blob_name, client=None, encryption_key=None, generation=None, **kwargs
      ):
          
          blob = Blob(
              bucket=self,
              name=blob_name,
              encryption_key=encryption_key,
              generation=generation,
              **kwargs
          )
          try:
              # NOTE: This will not fail immediately in a batch. However, when
              #       Batch.finish() is called, the resulting `NotFound` will be
              #       raised.
              blob.reload(client=client)
          except NotFound:
              return None
          else:
              return blob
docs: Get a blob object by name.
  
          This will return None if the blob doesn't exist:
  
          .. literalinclude:: snippets.py
            :start-after: [START get_blob]
            :end-before: [END get_blob]
  
          If :attr:`user_project` is set, bills the API request to that project.
  
          :type blob_name: str
          :param blob_name: The name of the blob to retrieve.
  
          :type client: :class:`~google.cloud.storage.client.Client` or
                        ``NoneType``
          :param client: Optional. The client to use.  If not passed, falls back
                         to the ``client`` stored on the current bucket.
  
          :type encryption_key: bytes
          :param encryption_key:
              Optional 32 byte encryption key for customer-supplied encryption.
              See
              https://cloud.google.com/storage/docs/encryption#customer-supplied.
  
          :type generation: long
          :param generation: Optional. If present, selects a specific revision of
                             this object.
  
          :type kwargs: dict
          :param kwargs: Keyword arguments to pass to the
                         :class:`~google.cloud.storage.blob.Blob` constructor.
  
          :rtype: :class:`google.cloud.storage.blob.Blob` or None
          :returns: The blob object if it exists, otherwise None.