code: def hstr(self, places=2, warn=True):
          
          if warn and self.preference != 'hours':
              raise WrongUnitError('hstr')
          if self.radians.size == 0:
              return '<Angle []>'
          hours = self._hours
          shape = getattr(hours, 'shape', ())
          if shape and shape != (1,):
              return "{0} values from {1} to {2}".format(
                  len(hours),
                  _hstr(min(hours), places),
                  _hstr(max(hours), places),
                  )
          return _hstr(hours, places)
docs: Convert to a string like ``12h 07m 30.00s``.