code: def lp7(self, reaction_subset):
          
  
          if self._zl is None:
              self._add_maximization_vars()
  
          positive = set(reaction_subset) - self._flipped
          negative = set(reaction_subset) & self._flipped
  
          v = self._v.set(positive)
          zl = self._zl.set(positive)
          cs = self._prob.add_linear_constraints(v >= zl)
          self._temp_constr.extend(cs)
  
          v = self._v.set(negative)
          zl = self._zl.set(negative)
          cs = self._prob.add_linear_constraints(v <= -zl)
          self._temp_constr.extend(cs)
  
          self._prob.set_objective(self._zl.sum(reaction_subset))
  
          self._solve()
docs: Approximately maximize the number of reaction with flux.
  
          This is similar to FBA but approximately maximizing the number of
          reactions in subset with flux > epsilon, instead of just maximizing the
          flux of one particular reaction. LP7 prefers "flux splitting" over
          "flux concentrating".