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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_tmp_gcs_bucket(cls, writer_spec):
 """Returns bucket used for writing tmp files."""

    if cls.TMP_BUCKET_NAME_PARAM in writer_spec:
      return writer_spec[cls.TMP_BUCKET_NAME_PARAM]
    return cls._get_gcs_bucket(writer_spec)