Shorthand way to return values that might be null

Problem: Suppose we have get-only property as below. In this we have a private variable and a public property both are list type.

private List<User> _usr ;         public List<User> lst         {             get             {                 if (_usr == null)                 {                     _usr = new List<User>();                 }                 return _usr;             }         }

How can I optimize this code or any shorthand way to write code of above scenario?

Answer: Yes we can, there are many way to write code in short to above code.

private List<User> _usr ;         public List<User> lst         {             get             {                 _usr = _usr ?? new List<User>();                 return _usr;             }         }

Or

private List<User> _usr ;         public List<User> lst         {             get{return _usr ?? (new List<User>());}         }