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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def elapsed(func):
 """A decorator for calculating time elapsed when execute function"""


    @functools.wraps(func)
    def wrapper(*args, **kw):
        start = time.time()
        print('Running `%s()` ...' % func.__name__)
        res = func(*args, **kw)
        end = time.time()
        print('Function `%s()` running elapsed %.2f s' %
              (func.__name__, end - start))
        return res

    return wrapper