diff --git a/src/api/api_seq.cpp b/src/api/api_seq.cpp
index ac65ab1f380..01e93235305 100644
--- a/src/api/api_seq.cpp
+++ b/src/api/api_seq.cpp
@@ -190,7 +190,7 @@ extern "C" {
             if (ch <= 32 || ch >= 127) {
                 buff.reset();
                 buffer.push_back('\\');
-                buffer.push_back('\\');  // possibly replace by native non-escaped version?
+//                buffer.push_back('\\');  // possibly replace by native non-escaped version?
                 buffer.push_back('u');
                 buffer.push_back('{');
                 while (ch > 0) {
diff --git a/src/api/python/z3/z3.py b/src/api/python/z3/z3.py
index 3f051865041..5c0d5765aee 100644
--- a/src/api/python/z3/z3.py
+++ b/src/api/python/z3/z3.py
@@ -10706,12 +10706,11 @@ def is_string_value(a):
     """
     return isinstance(a, SeqRef) and a.is_string_value()
 
-
 def StringVal(s, ctx=None):
     """create a string expression"""
-    s = "".join(str(ch) if ord(ch) < 128 else "\\u{%x}" % (ord(ch)) for ch in s)
+    s = "".join(str(ch) if 32 <= ord(ch) and ord(ch) < 127 else "\\u{%x}" % (ord(ch)) for ch in s)
     ctx = _get_ctx(ctx)
-    return SeqRef(Z3_mk_lstring(ctx.ref(), len(s), s), ctx)
+    return SeqRef(Z3_mk_string(ctx.ref(), s), ctx)
 
 
 def String(name, ctx=None):