def wf_notificant_id?(id)
      return true if id.is_a?(String) && id =~ /^\w{16}$/
      raise Wavefront::Exception::InvalidNotificantId
    end
def wf_notificant_id?(id)
      return true if id.is_a?(String) && id =~ /^\w{16}$/
      raise Wavefront::Exception::InvalidNotificantId
    end
Ensure the given argument is a valid Wavefront notificant ID.

 @param id [String] the notificant ID to validate
 @return True if the notificant ID is valid
 @raise Wavefront::Exception::InvalidNotificantId if the
   notificant ID is not valid