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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 _get_bigquery_service(self):
 """ Connect to the BigQuery service. Calling ``GoogleCredentials.get_application_default`` requires that you either be running in the Google Cloud, or have the ``GOOGLE_APPLICATION_CREDENTIALS`` environment variable set to the path to a credentials JSON file. :return: authenticated BigQuery service connection object :rtype: `googleapiclient.discovery.Resource <http://google.github.io/\ google-api-python-client/docs/epy/googleapiclient.discovery.\ Resource-class.html>`_ """

        logger.debug('Getting Google Credentials')
        credentials = GoogleCredentials.get_application_default()
        logger.debug('Building BigQuery service instance')
        bigquery_service = build('bigquery', 'v2', credentials=credentials)
        return bigquery_service