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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 save(self, filename, incl_uniqueid=False, compact=False):
 """ Save the ParameterSet to a JSON-formatted ASCII file :parameter str filename: relative or fullpath to the file :parameter bool incl_uniqueid: whether to including uniqueids in the file (only needed if its necessary to maintain the uniqueids when reloading) :parameter bool compact: whether to use compact file-formatting (maybe be quicker to save/load, but not as easily readable) :return: filename :rtype: str """

        filename = os.path.expanduser(filename)
        f = open(filename, 'w')
        if compact:
            if _can_ujson:
                ujson.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                           sort_keys=False, indent=0)
            else:
                logger.warning("for faster compact saving, install ujson")
                json.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                          sort_keys=False, indent=0)
        else:
            json.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                      sort_keys=True, indent=0, separators=(',', ': '))
        f.close()

        return filename