code: def get_f_ty_callback(self):
          
          cb = self._callback_factory(self.exprs)
          lb = self.lower_bounds
          ub = self.upper_bounds
          if lb is not None or ub is not None:
              def _bounds_wrapper(t, y, p=(), be=None):
                  if lb is not None:
                      if np.any(y < lb - 10*self._current_integration_kwargs['atol']):
                          raise RecoverableError
                      y = np.array(y)
                      y[y < lb] = lb[y < lb]
                  if ub is not None:
                      if np.any(y > ub + 10*self._current_integration_kwargs['atol']):
                          raise RecoverableError
                      y = np.array(y)
                      y[y > ub] = ub[y > ub]
                  return cb(t, y, p, be)
              return _bounds_wrapper
          else:
              return cb
docs: Generates a callback for evaluating ``self.exprs``.