code: func (s *SkipList) Get(key interface{}) (value interface{}, ok bool) {
  	candidate := s.getPath(s.header, nil, key)
  
  	if candidate == nil || candidate.key != key {
  		return nil, false
  	}
  
  	return candidate.value, true
  }
docs: // Get returns the value associated with key from s (nil if the key is
  // not present in s). The second return value is true when the key is
  // present.