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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 to_utf8(datas):
 """ Force utf8 string entries in the given datas """

    res = datas
    if isinstance(datas, dict):
        res = {}
        for key, value in datas.items():
            key = to_utf8(key)
            value = to_utf8(value)
            res[key] = value

    elif isinstance(datas, (list, tuple)):
        res = []
        for data in datas:
            res.append(to_utf8(data))

    elif isinstance(datas, unicode):
        res = datas.encode('utf-8')

    return res