Use default hash method to return hash value of bytes.

        :type py_bytes: binary_type
        :param py_bytes: a binary object

def of_bytes(self, py_bytes):
        """
        Use default hash method to return hash value of bytes.

        :type py_bytes: binary_type
        :param py_bytes: a binary object
        """
        m = self.hash_algo()
        m.update(py_bytes)
        return self.digest(m)