import functools
import time


def timer(func):
    """Print the runtime of the decorated function"""

    @functools.wraps(func)
    def wrapper_timer(*args, **kwargs):
        start_time = time.perf_counter()  # 1
        value = func(*args, **kwargs)
        end_time = time.perf_counter()  # 2
        run_time = end_time - start_time  # 3
        print(f"Finished {func.__name__!r} in {run_time:.4f} secs")
        return value

    return wrapper_timer


def debug(func):
    """Print the function signature and return value"""

    @functools.wraps(func)
    def wrapper_debug(*args, **kwargs):
        args_repr = [repr(a) for a in args]  # 1
        kwargs_repr = [f"{k}={v!r}" for k, v in kwargs.items()]  # 2
        signature = ", ".join(args_repr + kwargs_repr)  # 3
        print(f"Calling {func.__name__}({signature})")
        value = func(*args, **kwargs)
        print(f"{func.__name__!r} returned {value!r}")  # 4
        return value

    return wrapper_debug


class TimeWaster:
    @debug
    def __init__(self, max_num):
        self.max_num = max_num

    @timer
    def waste_time(self, num_times):
        for _ in range(num_times):
            sum([i ** 2 for i in range(self.max_num)])


tw = TimeWaster(1000)

tw.waste_time(999)