set/set.go
func (s *Set) Remove(value interface{}) {
	s.Lock()
	defer s.Unlock()
	delete(s.m, value)
}
func (s *Set) Remove(value interface{}) {
	s.Lock()
	defer s.Unlock()
	delete(s.m, value)
}
// Remove removes value from the set if it exists in the set.