diff --git a/lib/ace/mode/python_highlight_rules.js b/lib/ace/mode/python_highlight_rules.js
index f0c309d0..cc2b4266 100644
--- a/lib/ace/mode/python_highlight_rules.js
+++ b/lib/ace/mode/python_highlight_rules.js
@@ -72,7 +72,7 @@ PythonHighlightRules = function() {
         ("").split("|")
     );
 
-    var strPre = "(?:(?:[rubRUB])|(?:[ubUB][rR]))?";
+    var strPre = "(?:r|u|ur|R|U|UR|Ur|uR)?";
 
     var decimalInteger = "(?:(?:[1-9]\\d*)|(?:0))";
     var octInteger = "(?:0[oO]?[0-7]+)";
@@ -93,24 +93,24 @@ PythonHighlightRules = function() {
             regex : "#.*$"
         }, {
             token : "string",           // """ string
-            regex : strPre + '"{3}(?:(?:.)|(?:^"{3}))*?"{3}'
+            regex : strPre + '"{3}(?:[^\\\\]|\\\\.)*?"{3}'
         }, {
             token : "string",           // multi line """ string start
             regex : strPre + '"{3}.*$',
             next : "qqstring"
         }, {
             token : "string",           // " string
-            regex : strPre + '"(?:(?:\\\\.)|(?:[^"\\\\]))*?"'
+            regex : strPre + '"(?:[^\\\\]|\\\\.)*?"'
         }, {
             token : "string",           // ''' string
-            regex : strPre + "'{3}(?:(?:.)|(?:^'{3}))*?'{3}"
+            regex : strPre + "'{3}(?:[^\\\\]|\\\\.)*?'{3}"
         }, {
             token : "string",           // multi line ''' string start
             regex : strPre + "'{3}.*$",
             next : "qstring"
         }, {
             token : "string",           // ' string
-            regex : strPre + "'(?:(?:\\\\.)|(?:[^'\\\\]))*?'"
+            regex : strPre + "'(?:[^\\\\]|\\\\.)*?'"
         }, {
             token : "constant.numeric", // imaginary
             regex : "(?:" + floatNumber + "|\\d+)[jJ]\\b"
@@ -153,8 +153,8 @@ PythonHighlightRules = function() {
             regex : "\\s+"
         } ],
         "qqstring" : [ {
-            token : "string",           // multi line """ string end
-            regex : '(?:^"{3})*?"{3}',
+            token : "string", // multi line """ string end
+            regex : '(?:[^\\\\]|\\\\.)*?"{3}',
             next : "start"
         }, {
             token : "string",
@@ -162,7 +162,7 @@ PythonHighlightRules = function() {
         } ],
         "qstring" : [ {
             token : "string",           // multi line ''' string end
-            regex : "(?:^'{3})*?'{3}",
+            regex : "(?:[^\\\\]|\\\\.)*?'{3}",
             next : "start"
         }, {
             token : "string",