docs: def md5_of_file(abspath):
      """Md5 value of a file.
      """
      chunk_size = 1024 * 1024
      m = hashlib.md5()
      with open(abspath, "rb") as f:
          while True:
              data = f.read(chunk_size)
              if not data:
                  break
              m.update(data)
      return m.hexdigest()