Code practice

当在非测试代码中使用 assert 时，妥善添加断言信息

>>> assert 1 == 0
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AssertionError

在大段的日志中，单独存在的 AssertionError 不利于日志检索和问题定位，所以添加上可读的断言信息是更推荐的做法。

# BAD
assert "hello" == "world"

# GOOD
assert "hello" == "world", "Hello is not equal to world"

eg:

assert isinstance(req, Request), "req must request"