code: def adjoint(self):
          
          if self.domain.exponent == 2.0 and self.range.exponent == 2.0:
              return self.inverse
          else:
              raise NotImplementedError(
                  'no adjoint defined for exponents ({}, {}) != (2, 2)'
                  ''.format(self.domain.exponent, self.range.exponent))
docs: Adjoint transform, equal to the inverse.
  
          See Also
          --------
          inverse