Autocomplete self/cls in class methods

[matthewbastien]

Is your feature request related to a problem? Please describe.
Not necessarily a problem, but there are IDEs such as PyCharm that offer a very helpful feature that auto-completes class arguments for you so that you don't have to type the full signature. This reduces the amount of code one has to write manually and would be very helpful if brought to Pyright.

Describe the solution you'd like
When typing the opening parenthesis in the following class method, the cls argument is required and should be entered automatically by Pyright:

class Foo:
    @classmethod
    def class_method(cls):

In this more basic method, the self argument is required and should be entered automatically by Pyright when the opening parenthesis is typed:

class Bar:
    def instance_method(self):

In fact, it would be even be better to have Pyright complete the full class definition for you when you ask it for completions on @classmethod. Perhaps even when you type def there could be snippets (or some equivalent) that will write all of the basic method boilerplate for you and allow you to enter a method name.

[erictraut]

Since this isn't a core type checking feature request, I'm going to transfer it to the pylance issue tracker.

[debonte]

Related: #2538

[judej]

Moving this issue to discussion as an enhancement request for comments and upvotes.