How to use the rebound.clibrebound.reb_get_next_message function in rebound

def process_messages(self):
        clibrebound.reb_get_next_message.restype = c_int
        buf = create_string_buffer(c_int.in_dll(clibrebound, "reb_max_messages_length").value)
        while clibrebound.reb_get_next_message(byref(self), buf):
            msg = buf.value.decode("ascii")
            if msg[0]=='w':
                warnings.warn(msg[1:], RuntimeWarning)
            elif msg[0]=='e':
                raise RuntimeError(msg[1:])

def process_messages(self):
        clibrebound.reb_get_next_message.restype = c_int
        buf = create_string_buffer(c_int.in_dll(clibrebound, "reb_max_messages_length").value)
        while clibrebound.reb_get_next_message(byref(self), buf):
            msg = buf.value.decode("ascii")
            if msg[0]=='w':
                warnings.warn(msg[1:], RuntimeWarning)
            elif msg[0]=='e':
                raise RuntimeError(msg[1:])