i have a some problems understanding the following Code.
I have a class inside a class (it was given that way and we should use it like this) and i want to use the Fitter class to change the vocabulary attribute of the Tokenizer class.

The problem is i dont understand how i can access the Parent Objekt.

Here is the code of my classes:

class Tokenizer(TokenizerABC):
def __init__(
    self,
    vocabulary,
    pre_tokenizer
):
    self._vocabulary = vocabulary
    self._pre_tokenizer = pre_tokenizer

class Fitter(TokenizerABC.Fitter["Tokenizer"]):
    """A builder-style object for fitting a tokenizer to a corpus."""
    def __init__(self, lowercase=False, limit=None):
        ...


    def fit(self, corpus: list[str]) -> TokenizerABC:
        """Fit a tokenizer to the given corpus.

        Args:
            corpus (list[str]): The corpus to fit the tokenizer to.

        Returns:
            Parent (Generic[TokenizerABC]): The fitted tokenizer.
        """
        # some code

        vocabulary = # some code

        return ...

@classmethod
def fitter(cls) -> 'Tokenizer.Fitter':# -> Fitter[Self]:
    """Create a new Fitter object for this tokenizer.

    Returns:
        Fitter[Self]: The Fitter object for this tokenizer.
    """
    return ...

And in the test code he initializes the Objekts with:

abcd = ["a a a b", "c c c d d"]
tokenizer = Tokenizer.fitter().fit(abcd)

I use Python 3.12