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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 unhook(self, addr):
 """ Remove a hook. :param addr: The address of the hook. """

        if not self.is_hooked(addr):
            l.warning("Address %s not hooked", self._addr_to_str(addr))
            return

        del self._sim_procedures[addr]