diff --git a/syntax/python.vim b/syntax/python.vim
index 86b22c1..2524aba 100644
--- a/syntax/python.vim
+++ b/syntax/python.vim
@@ -114,7 +114,7 @@ endif
 "
 syn keyword pythonOperator      and in is not or
 if s:Enabled('g:python_highlight_operators')
-    syn match pythonOperator        '\V=\|-\|+\|*\|@\|/\|%\|&\||\|^\|~\|<\|>\|!='
+    syn match pythonOperator        '\V=\|-\|+\|*\|@\|/\|%\|&\||\|^\|~\|<\|>\|!=\|:='
 endif
 syn match pythonError           '[$?]\|\([-+@%&|^~]\)\1\{1,}\|\([=*/<>]\)\2\{2,}\|\([+@/%&|^~<>]\)\3\@![-+*@/%&|^~<>]\|\*\*[*@/%&|^<>]\|=[*@/%&|^<>]\|-[+*@/%&|^~<]\|[<!>]\+=\{2,}\|!\{2,}=\+' display
 
diff --git a/tests/test.py b/tests/test.py
index 61b91a1..c0f81ac 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -182,7 +182,7 @@ and or in is not
 < <= == != >= >
 
 = =- =+ =~
--= += *= **= @= /= //= %=
+-= += *= **= @= /= //= %= :=
 &= |= ^= ~= <<= >>=
 
 ->