code: def rand_bytes(length):
      
  
      if not isinstance(length, int_types):
          raise TypeError(pretty_message(
              '''
              length must be an integer, not %s
              ''',
              type_name(length)
          ))
  
      if length < 1:
          raise ValueError('length must be greater than 0')
  
      if length > 1024:
          raise ValueError('length must not be greater than 1024')
  
      return os.urandom(length)
docs: Returns a number of random bytes suitable for cryptographic purposes
  
      :param length:
          The desired number of bytes
  
      :raises:
          ValueError - when any of the parameters contain an invalid value
          TypeError - when any of the parameters are of the wrong type
          OSError - when an error is returned by OpenSSL
  
      :return:
          A byte string