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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:
 async def main():
 """`sublemon` library example!"""

    for c in (1, 2, 4,):
        async with Sublemon(max_concurrency=c) as s:
            start = time.perf_counter()
            await asyncio.gather(one(s), two(s))
            end = time.perf_counter()
            print('Limiting to', c, 'concurrent subprocess(es) took',
                  end-start, 'seconds\n')