diff --git a/syntax/python.vim b/syntax/python.vim
index 3ea261c..8be831b 100644
--- a/syntax/python.vim
+++ b/syntax/python.vim
@@ -103,7 +103,7 @@ syn keyword pythonOperator      and in is not or
 if s:Enabled('g:python_highlight_operators')
     syn match pythonOperator        '\V=\|-\|+\|*\|@\|/\|%\|&\||\|^\|~\|<\|>\|!='
 endif
-syn match pythonError           '[$?]\|\([-+@%&|^~]\)\1\{1,}\|\([=*/<>]\)\2\{2,}\|\([+=*@/%&|^~<>]\)\3\@![-+*@/%&|^~<>]\|-[+*@/%&|^~<]\|[<!>]\+=\{2,}\|!\{2,}=\+' display
+syn match pythonError           '[$?]\|\([-+@%&|^~]\)\1\{1,}\|\([=*/<>]\)\2\{2,}\|\([+*@/%&|^~<>]\)\3\@![-+*@/%&|^~<>]\|=[*@/%&|^<>]\|-[+*@/%&|^~<]\|[<!>]\+=\{2,}\|!\{2,}=\+' display
 
 "
 " Decorators (new in Python 2.4)
diff --git a/tests/test.py b/tests/test.py
index a9d088d..ff87a35 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -166,7 +166,7 @@ and or in is not
 & | ^ ~ << >>
 < <= == != >= >
 
-=
+= =- =+ =~
 -= += *= **= @= /= //= %=
 &= |= ^= ~= <<= >>=