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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 memorized_ttinfo(*args):
    '''Create only one instance of each distinct tuple'''
    try:
        return _ttinfo_cache[args]
    except KeyError:
        ttinfo = (
                memorized_timedelta(args[0]),
                memorized_timedelta(args[1]),
                args[2]
                )
        _ttinfo_cache[args] = ttinfo
        return ttinfo