Mypy doesn't consider the if condition

I have a dictionary with different types, and in my code, while reading the dictionary through a loop, based on the type of it, I have different operations. The code is working as expected, but MYPY is complaining that it is incorrect. Here is the sample code:

COL = {"ABC": ["col1","col2","col3",    ],"BBC": ["col1","col2","col3",    ],"XYZ": {"col1": "c1","col2": "c2","col3": "c3",    },}list(COL[table_name].keys()) if isinstance(COL[table_name], dict) else COL[table_name]

Mypy reports the error: error: "Collection[str]" has no attribute "values"

It looks like the if condition was not taken into consideration.

Tried type annotations for COL but did not work.