def METHOD_NAME(self):
    campaign = CampaignTrackingInfo(
        source='test_source with spaces',
        medium='test_medium',
        campaign='test_campaign',
        term='test_term',
        content='test_content'
    )
    self.assert_query_string_equal(
        'utm_source=test_source%20with%20spaces&utm_medium=test_medium&utm_campaign=test_campaign'
        '&utm_term=test_term&utm_content=test_content',
        campaign.to_query_string(),
    )