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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 del_permission(self, name):
 """ Deletes a permission from the backend, model permission :param name: """

        perm = self.find_permission(name)
        if perm:
            try:
                self.get_session.delete(perm)
                self.get_session.commit()
            except Exception as e:
                log.error(c.LOGMSG_ERR_SEC_DEL_PERMISSION.format(str(e)))
                self.get_session.rollback()