diff -r 1555e7776321 Lib/idlelib/colorizer.py
--- a/Lib/idlelib/colorizer.py	Fri Feb 10 12:37:21 2017 +0100
+++ b/Lib/idlelib/colorizer.py	Fri Mar 03 02:05:57 2017 -0500
@@ -13,7 +13,7 @@
     return "(?P<%s>" % name + "|".join(alternates) + ")"
 
 def make_pat():
-    kw = r"\b" + any("KEYWORD", keyword.kwlist) + r"\b"
+    kw = r"\b" + any("KEYWORD", keyword.kwlist + ['async', 'await']) + r"\b"
     builtinlist = [str(name) for name in dir(builtins)
                                         if not name.startswith('_') and \
                                         name not in keyword.kwlist]
@@ -265,6 +265,7 @@
     source = ("# Following has syntax errors\n"
         "if True: then int 1\nelif False: print 0\nelse: float(None)\n"
         "if iF + If + IF: 'keywork matching must respect case'\n"
+        "async def f(): await g()\n"
         "# All valid prefixes for unicode and byte strings should be colored\n"
         "'x', '''x''', \"x\", \"\"\"x\"\"\"\n"
         "r'x', u'x', R'x', U'x', f'x', F'x', ur'is invalid'\n"