code: def inverse(self):
          
          sign = '+' if self.sign == '-' else '-'
          return FourierTransform(
              domain=self.range, range=self.domain, impl=self.impl,
              axes=self.axes, halfcomplex=self.halfcomplex, shift=self.shifts,
              sign=sign, tmp_r=self._tmp_r, tmp_f=self._tmp_f)
docs: Inverse of the inverse, the forward FT.