python decorator to measure the execution time of a function

example.py

import time
from functools import wraps

def timer(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        if not hasattr(wrapper, 'total_time'):
            wrapper.total_time = 0
        _start = time.perf_counter()
        _result = func(*args, **kwargs)
        _end = time.perf_counter()
        _duration = _end - _start
        wrapper.total_time += _duration
        print(f"fn '{func.__name__}' = {_duration:.4f}", end=" - ")
        print(f"cumul : {wrapper.total_time:.4f}")
        return _result
    return wrapper

@timer
def test():
    time.sleep(1)


test()  # fn 'test' = 1.0045 - cumul : 1.0045
test()  # fn 'test' = 1.0030 - cumul : 2.0075