code: def _call(self, x):
          
  
          sum_constr = abs(x.ufuncs.sum() / self.diameter - 1) <= self.sum_rtol
  
          nonneq_constr = x.ufuncs.greater_equal(0).asarray().all()
  
          if sum_constr and nonneq_constr:
              return 0
          else:
              return np.inf
docs: Return ``self(x)``.