'Delete the documents with the corresponding document ids from the index.
If no document exists for the identifier in the list, then that document
identifier is ignored.
Args:
document_ids: A single identifier or list of identifiers of documents
to delete.
Kwargs:
deadline: Deadline for RPC call in seconds; if None use the default.
Raises:
DeleteError: If one or more documents failed to remove or
number removed did not match requested.
ValueError: If document_ids is not a string or iterable of valid document
identifiers or number of document ids is larger than
MAXIMUM_DOCUMENTS_PER_PUT_REQUEST or deadline is a negative number.'

@datastore_rpc._positional(2)
def delete(self, document_ids, deadline=None):

    return self.delete_async(document_ids, deadline=deadline).get_result()
