docs: def seed(data, entropy=None):
      """
          Seeds random generator with data.
          If entropy is not None, it should be floating point(double)
          value estimating amount of entropy  in the data (in bytes).
      """
      if not isinstance(data, bintype):
          raise TypeError("A string is expected")
      ptr = c_char_p(data)
      size = len(data)
      if entropy is None:
          libcrypto.RAND_seed(ptr, size)
      else:
          libcrypto.RAND_add(ptr, size, entropy)