code: func (nat *NAT) Mappings() []Mapping {
  	nat.mappingmu.Lock()
  	maps2 := make([]Mapping, 0, len(nat.mappings))
  	for m := range nat.mappings {
  		maps2 = append(maps2, m)
  	}
  	nat.mappingmu.Unlock()
  	return maps2
  }
docs: // Mappings returns a slice of all NAT mappings