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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 serialize_dictionary(dictionary):
 """Function to stringify a dictionary recursively. :param dictionary: The dictionary. :type dictionary: dict :return: The string. :rtype: basestring """

    string_value = {}
    for k, v in list(dictionary.items()):
        if isinstance(v, QUrl):
            string_value[k] = v.toString()
        elif isinstance(v, (QDate, QDateTime)):
            string_value[k] = v.toString(Qt.ISODate)
        elif isinstance(v, datetime):
            string_value[k] = v.isoformat()
        elif isinstance(v, date):
            string_value[k] = v.isoformat()
        elif isinstance(v, dict):
            # Recursive call
            string_value[k] = serialize_dictionary(v)
        else:
            string_value[k] = v
    return string_value