code: func (cn *connection) statusFlags() (ret string) {
  	c := func(b byte) {
  		ret += string([]byte{b})
  	}
  	if cn.Interested {
  		c('i')
  	}
  	if cn.Choked {
  		c('c')
  	}
  	c('-')
  	ret += cn.connectionFlags()
  	c('-')
  	if cn.PeerInterested {
  		c('i')
  	}
  	if cn.PeerChoked {
  		c('c')
  	}
  	return
  }
docs: // Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.