broken_trampoline.py

def trampoline(func):
    def decorated(*args):
        f = func(*args)
        while callable(f):
            f = f()
        return f
    return decorated

@trampoline
def fact(n, acc=1):
    if n == 1:
        return acc
    return lambda: fact(n - 1, n * acc)
    
# fact(1e4)