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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 standardize_mapping(into):
 """ Helper function to standardize a supplied mapping. .. versionadded:: 0.21.0 Parameters into : instance or subclass of collections.abc.Mapping Must be a class, an initialized collections.defaultdict, or an instance of a collections.abc.Mapping subclass. Returns ------- mapping : a collections.abc.Mapping subclass or other constructor a callable object that can accept an iterator to create the desired Mapping. See Also -------- DataFrame.to_dict Series.to_dict """

    if not inspect.isclass(into):
        if isinstance(into, collections.defaultdict):
            return partial(
                collections.defaultdict, into.default_factory)
        into = type(into)
    if not issubclass(into, abc.Mapping):
        raise TypeError('unsupported type: {into}'.format(into=into))
    elif into == collections.defaultdict:
        raise TypeError(
            'to_dict() only accepts initialized defaultdicts')
    return into