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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 get_config(self, slot, config_id):
 """Get a config variable assignment previously set on this sensor graph. Args: slot (SlotIdentifier):
 The slot that we are setting this config variable on. config_id (int):
 The 16-bit config variable identifier. Returns: (str, str|int):
 Returns a tuple with the type of the config variable and the value that is being set. Raises: ArgumentError: If the config variable is not currently set on the specified slot. """


        if slot not in self.config_database:
            raise ArgumentError("No config variables have been set on specified slot", slot=slot)

        if config_id not in self.config_database[slot]:
            raise ArgumentError("Config variable has not been set on specified slot", slot=slot, config_id=config_id)

        return self.config_database[slot][config_id]