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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 get_content_properties(self, content_id, expand=None, start=None, limit=None, callback=None):
 """ Returns a paginated list of content properties. Content properties are a key / value store of properties attached to a piece of Content. The key is a string, and the value is a JSON-serializable object. :param content_id (string):
 A string containing the id of the property content container. :param expand (string):
 OPTIONAL: A comma separated list of properties to expand on the content properties. Default: Empty. :param start (int):
 OPTIONAL: The start point of the collection to return. Default: None (0). :param limit (int):
 OPTIONAL: The limit of the number of items to return, this may be restricted by fixed system limits. Default: 10. :param callback: OPTIONAL: The callback to execute on the resulting data, before the method returns. Default: None (no callback, raw data returned). :return: The JSON data returned from the content/{id}/property endpoint, or the results of the callback. Will raise requests.HTTPError on bad input, potentially. """

        params = {}
        if expand:
            params["expand"] = expand
        if start is not None:
            params["start"] = int(start)
        if limit is not None:
            params["limit"] = int(limit)
        return self._service_get_request("rest/api/content/{id}/property".format(id=content_id),
                                         params=params, callback=callback)