Update type to follow newest typing spec

[guan404ming]

Why

• Do @overloads require an implementation in .pyi stubs ? python/typing#1838

The PEP is no longer normative. The current spec is https://typing.readthedocs.io/en/latest/spec/overload.html and it says pretty clearly that the implementation is required only in .py files.

How

• remove the overload in .pyi and add them in .py

---

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[guan404ming]

@eladkal Not sure whether it's still possible to also add this pr in 1.27.0 or we have to add it in 1.28.0. If could add it in 1.27.0, that would be great since we could test it in our amazon and slack migration.

[potiuk]

@eladkal Not sure whether it's still possible to also add this pr in 1.27.0 or we have to add it in 1.28.0. If could add it in 1.27.0, that would be great since we could test it in our amazon and slack migration.

I guess it is not breaking anything so we can easily defer it to 1.28.0