def wf_derivedmetric_id?(id)
      id = id.to_s if id.is_a?(Numeric)
      return true if id.is_a?(String) && id =~ /^\d{13}$/

      raise Wavefront::Exception::InvalidDerivedMetricId
    end
def wf_derivedmetric_id?(id)
      id = id.to_s if id.is_a?(Numeric)
      return true if id.is_a?(String) && id =~ /^\d{13}$/

      raise Wavefront::Exception::InvalidDerivedMetricId
    end
Ensure the given argument is a valid derived metric ID.  IDs
 are the millisecond epoch timestamp at which the derived
 metric was created.

 @param id [String, Integer]
 @return True if the ID is valid
 @raise Wavefront::Exception::InvalidDerivedMetricId