new_contents: # Copyright 2015 Novo Nordisk Foundation Center for Biosustainability, DTU.
  
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  
  # http://www.apache.org/licenses/LICENSE-2.0
  
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from sympy import And, Or
  
  
  def _str_or(self):
      return "(" + " OR ".join([str(v) for v in self.args]) + ")"
  
  Or.__str__ = _str_or
  
  
  def _str_and(self):
      return "(" + " AND ".join([str(v) for v in self.args]) + ")"
  
  And.__str__ = _str_and
subject: Patch sympy to return COBRA compatible expressions on str