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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 catalog(self, table='', column=''):
 """Lookup the values available for querying."""

        lookup_table = self.lookup_table
        if lookup_table is not None:
            if table:
                if column:
                    column = column.upper()
                    return lookup_table[table][column]
                return lookup_table[table]
            # Show what methods are available.
            return self.lookup_methods
        return None