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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 _defaultdict(dct, fallback=_illegal_character):
 """Wraps the given dictionary such that the given fallback function will be called when a nonexistent key is accessed. """

    out = defaultdict(lambda: fallback)
    for k, v in six.iteritems(dct):
        out[k] = v
    return out