Python Type Challenge - Level: intermediate, Topic: self

Challenge - self

3.12.7

type checker: pyright

Complete code following the instructions, so that lines followed by # expect-type-error (if any) fail type check, while others can pass.
Hit the "▶️ Run" button to see result.

💡 Read Hints

Check out Self——it's really easy, isn't it?
How about challenging yourself by using TypeVar instead?

Open Pyright Playground

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"""
TODO:
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`return_self` should return an instance of the same type as the current enclosed class.
"""
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import typing
​
​
class Foo:
    def return_self(self):
        ...
​
​

Stuck? Check out solution

xxxxxxxxxx
 
class SubclassOfFoo(Foo):
    pass
​
​
f: Foo = Foo().return_self()
sf: SubclassOfFoo = SubclassOfFoo().return_self()
​
sf: SubclassOfFoo = Foo().return_self()  # expect-type-error
​

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