code: func new(err error, msg string) *baseError {
  	stack := make([]uintptr, 200)
  	stackLength := runtime.Callers(3, stack)
  	return &baseError{
  		msg:   msg,
  		stack: stack[:stackLength],
  		inner: err,
  	}
  }
docs: // Internal helper function to create new baseError objects,
  // note that if there is more than one level of redirection to call this function,
  // stack frame information will include that level too.