code: func (m *randomReader) Read(b []byte) (int, error) {
  	for i := 0; i < len(b); {
  		binary.Write(m.b, binary.LittleEndian, m.r.Int63())
  		n, _ := m.b.Read(b[i:])
  		i += n
  	}
  
  	return len(b), nil
  }
docs: // Read will read random bytes from up to the length of b.