Reactive programming in python

reactive.py

from functools import wraps
from collections import defaultdict
from dataclasses import dataclass, field
from typing import Dict, List
import ast
import inspect

class StateFinder(ast.NodeVisitor):
    def __init__(self, state_name):
        self.state_name = state_name
        self.state_attrs = []

    def visit_Attribute(self, node):
        if node.value.id == self.state_name:
            self.state_attrs.append(node.attr)

@dataclass
class State:
    _subscribers: Dict[str, List] = field(default_factory=lambda: defaultdict(list))
    x: int = 3
    y: int = 1

    def __setattr__(self, key, val):
        super().__setattr__(key, val)
        for s in self._subscribers[key]:
            s()



def reactive(state_name):
    def wrapper(f):
        tree = ast.parse(inspect.getsource(f))
        sf = StateFinder(state_name)
        sf.visit(tree)
        for attr in sf.state_attrs:
            state._subscribers[attr].append(f)
        return f
    return wrapper

## WHOAA REACTIVE PROGRAMMING LETS GOOO

state = State()
@reactive('state')
def doprint():
    print(f'{state.x=}, {state.y=}')

state.x = 4
state.x = 5
state.y = 2