def chrono(f):
    def inner(lines):
        t0 = perf_counter()
        text = f(lines)
        elapsed = perf_counter() - t0
        print('%15s: %fs' % (f.__name__, elapsed))
        return text
    return inner
dataset/ETHPy150Open fluentpython/example-code/attic/sequences/str_concat.py/chrono/original