Creates the feed for DSA page URLs.

  Args:
    client: an AdWordsClient instance.

  Returns:
    A _DSAFeedDetails instance containing details about the created feed.

def _CreateFeed(client):
  """Creates the feed for DSA page URLs.

  Args:
    client: an AdWordsClient instance.

  Returns:
    A _DSAFeedDetails instance containing details about the created feed.
  """
  # Get the FeedService.
  feed_service = client.GetService('FeedService', version='v201809')

  # Create operation.
  operation = {
      # Create the feed.
      'operand': {
          'name': 'DSA Feed %s' % uuid.uuid4(),
          # Create attributes.
          'attributes': [
              {'type': 'URL_LIST', 'name': 'Page URL'},
              {'type': 'STRING_LIST', 'name': 'Label'}
          ],
          'origin': 'USER'
      },
      'operator': 'ADD'
  }

  # Add the feed.
  feed = feed_service.mutate([operation])['value'][0]
  return _DSAFeedDetails(feed['id'], feed['attributes'][0]['id'],
                         feed['attributes'][1]['id'])