See python-telegram-bot/python-telegram-bot#2262

overload_generator.py

import itertools
from collections import namedtuple
from typing import List

Arg = namedtuple('Arg', ['name', 'type_var', 'default'])

args = [
    Arg('context', 'CCT', 'CallbackContext'),
    # Order matters!
    Arg('user_data', 'UD', 'Dict'),
    Arg('chat_data', 'CD', 'Dict'),
    Arg('bot_data', 'BD', 'Dict'),
]


def annotation(arg: Arg, names: List[str]) -> str:
    if arg.name != 'context':
        return arg.type_var if arg.name in names else arg.default
    else:
        if arg.name in names:
            return arg.type_var
        base = arg.default
        user_data = 'UD' if 'user_data' in names else 'Dict'
        chat_data = 'CD' if 'chat_data' in names else 'Dict'
        bot_data = 'BD' if 'bot_data' in names else 'Dict'
        return f'{base}[{user_data}, {chat_data}, {bot_data}]'


present_args = []
for i in range(len(args) + 1):
    present_args.extend(list(itertools.combinations(args, i)))

outs = []
for combination in present_args:
    present_names = [a.name for a in combination]
    self_annotation = ', '.join([annotation(arg, present_names) for arg in args])
    self_annotation = f"self: 'ContextTypes[{self_annotation}]'"
    other_annotations = [
        f'{arg.name}: Type[{arg.type_var}]' for arg in args if arg.name in present_names
    ]
    complete_annotations = f'{self_annotation}, {", ".join(other_annotations)}'
    outs.append(f'@overload\ndef __init__({complete_annotations}): ...')

with open('output.txt', 'w') as file:
    file.write('\n'.join(outs))