code: func RandomAddressAt(self Address, prox int) (addr Address) {
  	addr = self
  	pos := -1
  	if prox >= 0 {
  		pos = prox / 8
  		trans := prox % 8
  		transbytea := byte(0)
  		for j := 0; j <= trans; j++ {
  			transbytea |= 1 << uint8(7-j)
  		}
  		flipbyte := byte(1 << uint8(7-trans))
  		transbyteb := transbytea ^ byte(255)
  		randbyte := byte(rand.Intn(255))
  		addr[pos] = ((addr[pos] & transbytea) ^ flipbyte) | randbyte&transbyteb
  	}
  	for i := pos + 1; i < len(addr); i++ {
  		addr[i] = byte(rand.Intn(255))
  	}
  
  	return
  }
docs: // RandomAddressAt (address, prox) generates a random address
  // at proximity order prox relative to address
  // if prox is negative a random address is generated