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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 asyncPipeSubstr(context=None, _INPUT=None, conf=None, **kwargs):
 """A string module that asynchronously returns a substring. Loopable. Parameters context : pipe2py.Context object _INPUT : twisted Deferred iterable of items or strings conf : { 'from': {'type': 'number', value': <starting position>}, 'length': {'type': 'number', 'value': <count of characters to return>} } returns ------- _OUTPUT : twisted.internet.defer.Deferred generator of substrings """

    conf['start'] = conf.pop('from', dict.get(conf, 'start'))
    splits = yield asyncGetSplits(_INPUT, conf, **cdicts(opts, kwargs))
    parsed = yield asyncDispatch(splits, *get_async_dispatch_funcs())
    _OUTPUT = yield asyncStarMap(partial(maybeDeferred, parse_result), parsed)
    returnValue(iter(_OUTPUT))