Here's a case where `inspect.getsource` returns the wrong class definition when a file contains multiple class definitions with the same name. This pattern is valid runtime behavior when the class definitions are inside different scopes (e.g. a factory pattern where classes are defined and returned inside a function).

```
import inspect


def foo0():
    class Foo:
        x = 4
    return Foo


def foo1():
    class Foo:
        x = 5
    return Foo


print(inspect.getsource(foo1()))

print(foo1().x)
print(foo0().x)
```

Running this file produces
```
❯ python inspect-getsource-issue.py
    class Foo:
        x = 4

5
4
```

Turns out this is a documented issue in the source code: https://github.com/python/cpython/blob/3.7/Lib/inspect.py#L794-L796

I think findsource could be made more robust by using __qualname__ if it available.

This looks like a duplicate of https://bugs.python.org/issue35113 . I have created a PR for the issue but didn't have time to debug the Windows issue.

Closing it as duplicate of issue35113.