[Python] Is it possible to create groups/layers in method chaining in Python?

I am aware that I can use method chaining by simply having methods return self, e.g.

object.routine1().routine2().routine3()


But is it possible to organize methods into layers or groups when applying method chaining? e.g.

object.Layer1.routine1().routine2().Layer2.routine3()


The context is that I am trying to build a text analytics pipeline and the different layers would correspond to text level, sentence level and token level preprocessing steps. So what I am trying to build is something like this

text = "This is an example foo text with some special characters!!!! And some sentences"

pr = TextPreprocessor(text)
processed_text = (
pr.text_level.lower_case()
.sentence_level.split_sentences().remove_special_characters()
.token_level.tokenize()
.text
)


This is the code that almost (!) gets the text processing example to work:

import re

class TextLevelPreprocessor:
def __init__(self, parent):
self.parent = parent

def lower_case(self):
self.parent.text = self.parent.text.lower()
return self.parent

class SentenceLevelPreprocessor:
def __init__(self, parent):
self.parent = parent

def split_sentences(self):
self.parent.text = self.parent.text.split('. ')
return self.parent

def remove_special_characters(self):
self.parent.text = [re.sub('[!@#$]', '', s) for s in self.parent.text]
return self.parent

class TokenLevelPreprocessor:
def __init__(self, parent):
self.parent = parent

def tokenize(self):
self.parent.text = [t.split() for t in self.parent.text]
return self.parent

class TextPreprocessor:
def __init__(self, text):
self.text = text
self.text_level = TextLevelPreprocessor(self)
self.sentence_level = SentenceLevelPreprocessor(self)
self.token_level = TokenLevelPreprocessor(self)


However here only this syntax would work

pr = TextPreprocessor(text)
processed_text = (
pr.text_level.lower_case()
.sentence_level.split_sentences().
.sentence_level.remove_special_characters()
.token_level.tokenize()
.text
)


which would mean that one would have to add the "Layer" or "Group" everytime one uses a method, which seems verbose.

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