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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 remove(self, symbol):
 """ Remove the entry for the unit matching `symbol`. Parameters symbol : str The name of the unit symbol to remove from the registry. """

        self._unit_system_id = None

        if symbol not in self.lut:
            raise SymbolNotFoundError(
                "Tried to remove the symbol '%s', but it does not exist "
                "in this registry." % symbol
            )

        del self.lut[symbol]