mypy rejects unpacking into same variable

Bug Report

I believe the following code should be fine, however mypy rejects the case where we're unpacking into the variable which was expanded:

foo: tuple[int, ...] = ()

# Ok
bar, *quox = foo

# Incompatible types in assignment (expression has type "List[int]", variable has type "Tuple[int, ...]")  [assignment]
bar, *foo = foo

There are a number of similar issues reported, the closest being https://github.com/python/mypy/issues/9706, however I believe this is distinct as it reproduces when the generic type is int (though my original code was using str). This suggests a different root cause.

Your Environment

• Mypy version used: 1.0.1
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: 3.10

Comienza ejecutando el fragmento de Python 3.10 indicado con mypy 1.0.1 y siguiendo cómo se comprueba la asignación por desempaquetado cuando la variable desempaquetada también es la fuente. Añade una prueba de regresión para este caso, asegurándote de que se acepte el desempaquetado de la misma variable mientras que las asignaciones incompatibles sigan siendo diagnosticadas.