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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_installed(self):
 """Saves the list of installed repo XML settings files."""

        import json
        from utility import json_serial, get_json
        #This is a little tricky because the data file doesn't just have a list
        #of installed servers. It also manages the script's database that tracks
        #the user's interactions with it.
        fulldata = get_json(self.instpath, {})
        fulldata["installed"] = self.installed
        with open(self.instpath, 'w') as f:
            json.dump(fulldata, f, default=json_serial)