Create the current document in the Firestore database.

        Args:
            document_data (dict): Property names and values to use for
                creating a document.

        Returns:
            google.cloud.firestore_v1beta1.types.WriteResult: The
            write result corresponding to the committed document. A write
            result contains an ``update_time`` field.

        Raises:
            ~google.cloud.exceptions.Conflict: If the document already exists.

def create(self, document_data):
        """Create the current document in the Firestore database.

        Args:
            document_data (dict): Property names and values to use for
                creating a document.

        Returns:
            google.cloud.firestore_v1beta1.types.WriteResult: The
            write result corresponding to the committed document. A write
            result contains an ``update_time`` field.

        Raises:
            ~google.cloud.exceptions.Conflict: If the document already exists.
        """
        batch = self._client.batch()
        batch.create(self, document_data)
        write_results = batch.commit()
        return _first_write_result(write_results)