using cProfile to profile a code with decorators have strange results

Question

So i'm using cProfile and snakeviz to profil my code. My code has decorator which seems to make the cProfile results not very correct :

my code :

import time
import decorator


@decorator.decorator
def my_deco(f, *args, **kwargs):
    ret = f(*args, **kwargs)
    return ret

def a():
    time.sleep(2)
    b()
    c()

@my_deco
def b():
    time.sleep(3)
    d()

@my_deco
def c():
    time.sleep(1)
    d()
    
@my_deco
def d():
    time.sleep(3)


if __name__ == "__main__":
    a()

profiling without decorator (expected behavior) : In this case, b, c are at the same level and d bellow.

profiling with decorator (not wanted behavior) : In this case, b, c and d are at the same level.