https://github.com/frictionlessdata/tableschema-bigquery-py#storage

def describe(self, bucket, descriptor=None):
        """https://github.com/frictionlessdata/tableschema-bigquery-py#storage
        """

        # Set descriptor
        if descriptor is not None:
            self.__descriptors[bucket] = descriptor

        # Get descriptor
        else:
            descriptor = self.__descriptors.get(bucket)
            if descriptor is None:
                table_name = self.__mapper.convert_bucket(bucket)
                response = self.__service.tables().get(
                    projectId=self.__project,
                    datasetId=self.__dataset,
                    tableId=table_name).execute()
                converted_descriptor = response['schema']
                descriptor = self.__mapper.restore_descriptor(converted_descriptor)

        return descriptor