code: def signed_dms(self, warn=True):
          
          if warn and self.preference != 'degrees':
              raise WrongUnitError('signed_dms')
          return _sexagesimalize_to_float(self._degrees)
docs: Convert to a tuple (degrees, hours, minutes, seconds).
  
          The ``sign`` will be either +1 or -1, and the other quantities
          will all be positive.