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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 destroy(self):
 """Destroys a session completely, by deleting all keys and removing it from the internal store immediately. This allows removing a session for security reasons, e.g. a login stored in a session will cease to exist if the session is destroyed. """

        for k in list(self.keys()):
            del self[k]

        if getattr(self, 'sid_s', None):
            current_app.kvsession_store.delete(self.sid_s)
            self.sid_s = None

        self.modified = False
        self.new = False