code: def fastcc_is_consistent(model, epsilon, solver):
      
      for reaction in fastcc(model, epsilon, solver):
          return False
      return True
docs: Quickly check whether model is consistent
  
      Return true if the model is consistent. If it is only necessary to know
      whether a model is consistent, this function is fast as it will return
      the result as soon as it finds a single inconsistent reaction.
  
      Args:
          model: :class:`MetabolicModel` to solve.
          epsilon: Flux threshold value.
          solver: LP solver instance to use.