code: def inverse_transform(self, maps):
          r
          y = maps[self._outputvar]
          out = {self._inputvar : self.logistic(y, self._a, self._b)}
          return self.format_output(maps, out)
docs: r"""Computes :math:`y = \mathrm{logistic}(x; a,b)`.
  
          The codomain :math:`a, b` of :math:`y` are given by the class's bounds.
  
          Parameters
          ----------
          maps : dict or FieldArray
              A dictionary or FieldArray which provides a map between the
              parameter name of the variable to transform and its value(s).
  
          Returns
          -------
          out : dict or FieldArray
              A map between the transformed variable name and value(s), along
              with the original variable name and value(s).