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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 export_artifacts(self, processed_artifacts, sketch_id):
 """Upload provided artifacts to specified, or new if non-existent, sketch. Args: processed_artifacts: List of (timeline_name, artifact_path) tuples sketch_id: ID of sketch to append the timeline to Returns: int: ID of sketch. """


    # Export processed timeline(s)
    for timeline_name, artifact_path in processed_artifacts:
      print('Uploading {0:s} to timeline {1:s}'.format(
          artifact_path, timeline_name))
      new_timeline_id = self.upload_timeline(timeline_name, artifact_path)
      self.add_timeline_to_sketch(sketch_id, new_timeline_id)

    return sketch_id