public List <OperatorStrips> Produce(PropertyStrips p, List <OperatorStrips> Availables)
        {
            var r = new List <OperatorStrips>();

            foreach (var op in Availables)
            {
                if (op.Produce(p))
                {
                    r.Add(op);
                }
            }
            return(r);
        }
 public bool Produce(PropertyStrips p)
 {
     return(_a.Contains(p));
 }