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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 init_defaults(self):
 """ Sets the default values for this instance """

        self.sql = ''
        self.tables = []
        self.joins = []
        self._where = Where()
        self.groups = []
        self.sorters = []
        self._limit = None
        self.table_prefix = ''
        self.is_inner = False
        self.with_tables = []
        self._distinct = False
        self.distinct_ons = []
        self.field_names = []
        self.field_names_pk = None
        self.values = []