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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _AddWebPageCriteria(client, ad_group_id):
 """Adds a web page criterion to target Dynamic Search Ads. Args: client: an AdWordsClient instance. ad_group_id: an integer ID of the ad group the criteria is being added to. """

  ad_group_criterion_service = client.GetService('AdGroupCriterionService',
                                                 version='v201809')

  operations = [{
      'operator': 'ADD',
      # Create biddable ad group criterion.
      'operand': {
          'xsi_type': 'BiddableAdGroupCriterion',
          'adGroupId': ad_group_id,
          # Create a webpage criterion for special offers for children.
          'criterion': {
              'xsi_type': 'Webpage',
              'parameter': {
                  'criterionName': 'Special offers for children.',
                  'conditions': [
                      {
                          'operand': 'URL',
                          'argument': '/marscruise/children'
                      },
                      {
                          'operand': 'PAGE_TITLE',
                          'argument': 'Special Offer'
                      }
                  ]
              }
          },
          'userStatus': 'PAUSED',
          # Optional: set a custom bid.
          'biddingStrategyConfiguration': {
              'bids': [{
                  'xsi_type': 'CpcBid',
                  'bid': {
                      'microAmount': 10000000L
                  }
              }]
          }
      }
  }]

  criterion = ad_group_criterion_service.mutate(operations)['value'][0]

  print 'Webpage criterion with ID "%d" was added to ad group ID "%d".' % (
      criterion['criterion']['id'], criterion['adGroupId'])