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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 group_dict(items, keyfunc):
 """Return a list defaultdict with ``items`` grouped by ``keyfunc``. [('e', ['e']), ('g', ['g', 'g']), ('s', ['s'])] """

    result = collections.defaultdict(list)
    for i in items:
        key = keyfunc(i)
        result[key].append(i)
    return result