def embargo_params
      return []           unless wants_embargo?
      raise ArgumentError unless valid_embargo?

      [release_date, (during || PRIVATE), (after || PUBLIC)]
    end
def embargo_params
      return []           unless wants_embargo?
      raise ArgumentError unless valid_embargo?

      [release_date, (during || PRIVATE), (after || PUBLIC)]
    end
@param [String] after
 @param [String] during
 @param [String] release_date
 @param [String] visibility

 @return [Array] the parameters for the requested embargo