Convert to a string like ``181deg 52\' 30.0"``.

def dstr(self, places=1, warn=True):
        """Convert to a string like ``181deg 52\' 30.0"``."""
        if warn and self.preference != 'degrees':
            raise WrongUnitError('dstr')
        if self.radians.size == 0:
            return '<Angle []>'
        degrees = self._degrees
        signed = self.signed
        shape = getattr(degrees, 'shape', ())
        if shape and shape != (1,):
            return "{0} values from {1} to {2}".format(
                len(degrees),
                _dstr(min(degrees), places, signed),
                _dstr(max(degrees), places, signed),
                )
        return _dstr(degrees, places, signed)