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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 update_artifact_cache(self, vts_artifactfiles_pairs):
 """Write to the artifact cache, if we're configured to. vts_artifactfiles_pairs - a list of pairs (vts, artifactfiles) where - vts is single VersionedTargetSet. - artifactfiles is a list of absolute paths to artifacts for the VersionedTargetSet. """

    update_artifact_cache_work = self._get_update_artifact_cache_work(vts_artifactfiles_pairs)
    if update_artifact_cache_work:
      self.context.submit_background_work_chain([update_artifact_cache_work],
                                                parent_workunit_name='cache')