如何检查我的类型 t 是否被 typing.List 包围？ 例如检查 int 和 List[int] 之间的区别

Question

I want to execute different code depending on the type of my t .

I've got the follwing types:

from pydantic import BaseModel
from typing import List

class Person(BaseModel):
    name: str
    id: int

and

t1 = Person
t2 = List[Person]

now I want to check if my variable tX is if of a list type or a normal type. How can I do that?

def check_if_list(t):
    if type(t) == List:  # <- this doesn't work how can i do this check
        print('LIST') # some code
    else:
        print('NO LIST') # some code

t1 and t2 would give me:

check_if_list(t1)  # prints NO LIST
check_if_list(t2)  # prints LIST

Answer 1

You don't to import the typing library. Just evaluate this type(t) == list.

Answer 2

The most pythonic way of doing it is using the built-in function isinstance :

if isinstance(t, list)

At least according to PEP-8 :

Object type comparisons should always use isinstance() instead of comparing types directly

---

If you want to check an inheritance from typing.List you should be aware that a list doesn't come from typing.List , that's only a way of representing it in type hints.