import contextlib
import gc
import threading

_times_disabled = 0
gc_lock = threading.Lock()

@contextlib.contextmanager
def no_gc():
    global _times_disabled
    with gc_lock:
        if _times_disabled == 0:
            gc.disable()
        _times_disabled += 1
    try:
        yield
    finally:
        with gc_lock:
            _times_disabled -= 1
            if _times_disabled == 0:
                gc.enable()