Python: Remove unnecessary 'exists'.

python/ql/lib/semmle/python/PrintAst.qll

@@ -52,8 +52,7 @@ private newtype TPrintAstNode =
   TStmtListNode(StmtList list) {
     shouldPrint(list.getAnItem(), _) and
     not list = any(Module mod).getBody() and
-    not forall(AstNode child | child = list.getAnItem() | isNotNeeded(child)) and
-    exists(list.getAnItem())
+    not forall(AstNode child | child = list.getAnItem() | isNotNeeded(child))
   } or
   TRegExpTermNode(RegExpTerm term) {
     exists(StrConst str | term.getRootTerm() = getParsedRegExp(str) and shouldPrint(str, _))

python/ql/lib/semmle/python/dataflow/new/internal/PrintNode.qll

@@ -58,7 +58,6 @@ string prettyNode(DataFlow::Node node) {
  */
 bindingset[node]
 string prettyNodeForInlineTest(DataFlow::Node node) {
-  exists(node.asExpr()) and
   result = prettyExpr(node.asExpr())
   or
   exists(Expr e | e = node.(DataFlow::PostUpdateNode).getPreUpdateNode().asExpr() |