Make a ``Write`` protobuf for ``delete()`` methods.

    Args:
        document_path (str): A fully-qualified document path.
        option (optional[~.firestore_v1beta1.client.WriteOption]): A
           write option to make assertions / preconditions on the server
           state of the document before applying changes.

    Returns:
        google.cloud.firestore_v1beta1.types.Write: A
        ``Write`` protobuf instance for the ``delete()``.

def pb_for_delete(document_path, option):
    """Make a ``Write`` protobuf for ``delete()`` methods.

    Args:
        document_path (str): A fully-qualified document path.
        option (optional[~.firestore_v1beta1.client.WriteOption]): A
           write option to make assertions / preconditions on the server
           state of the document before applying changes.

    Returns:
        google.cloud.firestore_v1beta1.types.Write: A
        ``Write`` protobuf instance for the ``delete()``.
    """
    write_pb = write_pb2.Write(delete=document_path)
    if option is not None:
        option.modify_write(write_pb)

    return write_pb