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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_sql(self, value, clause):
 """ Add a WHERE clause to the state. :param value: The unknown to bind into the state. Uses SQLBuilder._map_value() to map this into an appropriate database compatible type. :param clause: A SQL fragment defining the restriction on the unknown value """

        if value is not None:
            self.sql_args.append(SQLBuilder.map_value(value))
            self.where_clauses.append(clause)