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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 _unicode_handler(obj):
 """ Transforms an unicode string into a UTF-8 equivalent. :param obj: object to transform into it's UTF-8 equivalent :return: the UTF-8 equivalent of the string """

    try:
        result = obj.isoformat()
    except AttributeError:
        raise TypeError("Unserializable object {} of type {}".format(obj,
                                                                     type(obj)))

    return result