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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 _fix_key(self, key):
 """ Appends the GCONF_PREFIX to the key if needed @param key: The key to check @type key: C{string} @returns: The fixed key @rtype: C{string} """

        if not key.startswith(self.GCONF_DIR):
            return self.GCONF_DIR + key
        else:
            return key