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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_sql(self):
 """ Builds and returns the WHERE portion of the sql :return: the WHERE portion of the sql :rtype: str """

        # reset arg index and args
        self.arg_index = 0
        self.args = {}

        # build the WHERE sql portion if needed
        if len(self.wheres):
            where = self.build_where_part(self.wheres)
            return 'WHERE {0} '.format(where)
        return ''