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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 _AddCampaignsToGroup(client, campaign_group_id, campaign_ids):
 """Adds multiple campaigns to a campaign group. Args: client: an AdWordsClient instance. campaign_group_id: an integer ID for the campaign group. campaign_ids: a list of integer IDs for campaigns. """

  # Get the CampaignService.
  campaign_service = client.GetService('CampaignService', version='v201809')

  # Create the operations.
  operations = [{
      'operator': 'SET',
      'operand': {
          'id': campaign_id,
          'campaignGroupId': campaign_group_id
      }
  } for campaign_id in campaign_ids]

  campaign_service.mutate(operations)

  # Display the results.
  print ('The following campaign IDs were added to the campaign group with ID '
         '"%d":\n\t%s' % (campaign_group_id, campaign_ids))