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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 removeSessionWithKey(self, key):
 """ Remove a persistent session, if it exists. @type key: L{bytes} @param key: The persistent session identifier. """

        self.store.query(
            PersistentSession,
            PersistentSession.sessionKey == key).deleteFromStore()