#vulnerable code 
                                public static void bindIter(@NotNull Scope s, Node target, @NotNull Node iter, Binding.Kind kind) {
        Type iterType = Node.resolveExpr(iter, s);

        if (iterType.isListType()) {
            bind(s, target, iterType.asListType().getElementType(), kind);
        } else if (iterType.isTupleType()) {
            bind(s, target, iterType.asTupleType().toListType().getElementType(), kind);
        } else {
            List<Binding> ents = iterType.getTable().lookupAttr("__iter__");
            for (Binding ent : ents) {
                if (ent == null || !ent.getType().isFuncType()) {
                    if (!iterType.isUnknownType()) {
                        iter.addWarning("not an iterable type: " + iterType);
                    }
                    bind(s, target, Indexer.idx.builtins.unknown, kind);
                } else {
                    bind(s, target, ent.getType().asFuncType().getReturnType(), kind);
                }
            }
        }
    } 
                            #location 10 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                public static void bindIter(@NotNull Scope s, Node target, @NotNull Node iter, Binding.Kind kind) {
        Type iterType = Node.resolveExpr(iter, s);

        if (iterType.isListType()) {
            bind(s, target, iterType.asListType().getElementType(), kind);
        } else if (iterType.isTupleType()) {
            bind(s, target, iterType.asTupleType().toListType().getElementType(), kind);
        } else {
            List<Binding> ents = iterType.getTable().lookupAttr("__iter__");
            if (ents != null) {
                for (Binding ent : ents) {
                    if (ent.getType().isFuncType()) {
                        bind(s, target, ent.getType().asFuncType().getReturnType(), kind);
                    } else {
                        iter.addWarning("not an iterable type: " + iterType);
                        bind(s, target, Indexer.idx.builtins.unknown, kind);
                    }
                }
            }
        }
    }