Method _gen_cols

django/db/models/sql/query.py:2040–2055

(cls, exprs, include_external=False, resolve_refs=True)

    @classmethod
    def _gen_cols(cls, exprs, include_external=False, resolve_refs=True):
        for expr in exprs:
            if isinstance(expr, Col):
                yield expr
            elif include_external and callable(
                getattr(expr, "get_external_cols", None)
            ):
                yield from expr.get_external_cols()
            elif hasattr(expr, "get_source_expressions"):
                if not resolve_refs and isinstance(expr, Ref):
                    continue
                yield from cls._gen_cols(
                    expr.get_source_expressions(),
                    include_external=include_external,
                    resolve_refs=resolve_refs,
                )

    @classmethod
    def _gen_col_aliases(cls, exprs):