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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_account_id(cls, writer_spec):
 """Returns the account id to use with tmp bucket."""

    # pick tmp id iff tmp bucket is set explicitly
    if cls.TMP_BUCKET_NAME_PARAM in writer_spec:
      return writer_spec.get(cls._TMP_ACCOUNT_ID_PARAM, None)
    return cls._get_account_id(writer_spec)