append str to list in dataclass

[flash77]

Dear community,

I'm trying to append str to a list, which is in a dataclass.
I'm totally new to dataclasses.
I used to use a textfile for storing strings.

Then I read about dataclasses for storing data.

What is the simplest way for appending string to a list in a dataclass?

When I try mylist: list = []
then it is said to use default_factory...

@dataclass
class C():
    mylist: list
    a: str

    def __post_init__(self):
        return self.mylist.append(self.a)


c = C("a")
print(c.mylist)
c = C("b")
print(c.mylist)

mylist should be ["a", "b"].

Thanks a lot for the help, I did a lot of googling, but with no success...