code: def trigger_pipeline(self, ref, token, variables={}, **kwargs):
          
          path = '/projects/%s/trigger/pipeline' % self.get_id()
          post_data = {'ref': ref, 'token': token, 'variables': variables}
          attrs = self.manager.gitlab.http_post(
              path, post_data=post_data, **kwargs)
          return ProjectPipeline(self.pipelines, attrs)
docs: Trigger a CI build.
  
          See https://gitlab.com/help/ci/triggers/README.md#trigger-a-build
  
          Args:
              ref (str): Commit to build; can be a branch name or a tag
              token (str): The trigger token
              variables (dict): Variables passed to the build script
              **kwargs: Extra options to send to the server (e.g. sudo)
  
          Raises:
              GitlabAuthenticationError: If authentication is not correct
              GitlabCreateError: If the server failed to perform the request