def validate_request_row_key(self, request):
if self.batch_row_keys:<EOL><INDENT>if self.get_request_row_key(request) in self.batch_row_keys:<EOL><INDENT>raise AzureBatchValidationError(_ERROR_DUPLICATE_ROW_KEY_IN_BATCH)<EOL><DEDENT><DEDENT>else:<EOL><INDENT>self.batch_row_keys.append(self.get_request_row_key(request))<EOL><DEDENT>
Validates that all requests have the different RowKey and adds RowKey
to existing RowKey list.

request:
    the request to insert, update or delete entity