Python context manager that is stack-aware in a thread safe manner

stacked_context.py

import threading, random


class StackContext:
    def __init__(self):
        self._state = threading.local()
        self._state.stack = []

    def __enter__(self):
        this_context = random.random()
        self._state.stack.append(this_context)
        print('enter', this_context)
        return this_context

    def __exit__(self, *args):
        this_context = self._state.stack.pop(-1)
        print('exit', this_context)


context = StackContext()

with context:
    with context:
        with context as inner:
            print(f'inner={inner}')