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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 mk_nested_dic(path, val, seps=PATH_SEPS):
 """ Make a nested dict iteratively. :param path: Path expression to make a nested dict :param val: Value to set :param seps: Separator char candidates {'a': {'b': {'c': 1}}} {'a': {'b': {'c': 1}}} """

    ret = None
    for key in reversed(_split_path(path, seps)):
        ret = {key: val if ret is None else ret.copy()}

    return ret