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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 delete_model(self, model):
 """Delete a specific session."""

        if SessionActivity.is_current(sid_s=model.sid_s):
            flash('You could not remove your current session', 'error')
            return
        delete_session(sid_s=model.sid_s)
        db.session.commit()