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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 add_override(self, addr, key, value):
 """Register an attribute override for a device."""

        address = Address(str(addr)).id
        _LOGGER.debug('New override for %s %s is %s', address, key, value)
        device_override = self._overrides.get(address, {})
        device_override[key] = value
        self._overrides[address] = device_override