Submit a populator batch

        Submit a populator batch as a series of HTTP requests in small chunks,
        returning the batch GUID, or raising exception on error.

def submit_populator_batch(self, column_name, batch):
        """Submit a populator batch

        Submit a populator batch as a series of HTTP requests in small chunks,
        returning the batch GUID, or raising exception on error."""
        if not set(column_name).issubset(_allowedCustomDimensionChars):
            raise ValueError('Invalid custom dimension name "%s": must only contain letters, digits, and underscores' % column_name)
        if len(column_name) < 3 or len(column_name) > 20:
            raise ValueError('Invalid value "%s": must be between 3-20 characters' % column_name)

        url = '%s/api/v5/batch/customdimensions/%s/populators' % (self.base_url, column_name)
        resp_json_dict = self._submit_batch(url, batch)
        if resp_json_dict.get('error') is not None:
            raise RuntimeError('Error received from server: %s' % resp_json_dict['error'])

        return resp_json_dict['guid']