code: func (s *Set) Intersection(other *Set) *Set {
  	result := new(Set)
  	if s == nil {
  		return result
  	}
  	if other != nil {
  		for _, v := range s.m {
  			if other.Include(v) {
  				result.Add(v)
  			}
  		}
  	}
  
  	return result
  }
docs: // Intersection computes the set intersection with other.