[Python] Using pattern matching with a class that inherits from str in Python 3.10

In a parser library I maintain, I have some classes that inherit from str to manage parsed strings and parsed symbols. This has been working well for a long time, but with Python 3.10, someone requested being able to use match and case on these classes. I have constructed an example script that shows how this is failing:

class Binge(str):
def __eq__(self, other):
return self.__class__ == other.__class__ and str.__eq__(self, other)

def __ne__(self, other):
return not self == other


# These two asserts are important for how the class is used
assert Binge('a') == Binge('a')
assert Binge('a') != 'a'

# What does it take to then make this work?
matched = False
match Binge("asdf"):
case Binge("asdf"):
matched = True
assert matched


If I add:

print(self.__class__, other.__class__)


in the __eq__ function, I see this:

<class '__main__.Binge'> <class 'str'>

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