diff --git a/todoist_taskwarrior/utils.py b/todoist_taskwarrior/utils.py
index 9456274..5cbcf3f 100644
--- a/todoist_taskwarrior/utils.py
+++ b/todoist_taskwarrior/utils.py
@@ -65,7 +65,16 @@ _PERIOD = r'(?P<period>hour|day|week|month|year)s?'
 _EVERY = r'ev(ery)?'
 _CYCLES = r'((?P<cycles>\d+)(st|nd|rd|th)?)'
 _SIMPLE = r'(?P<simple>daily|weekly|monthly|yearly)'
-_DOW = r'((?P<dayofweek>(mo(n(day)?)?|tu(e(s(day)?)?)?|we(d(s|(nes(day)?)?)?)?|th(u(rs(day)?)?)?|fr(i(day)?)?|sa(t(urday)?)?|su(n(day)?)?)))'
+_DOW = (
+    r'((?P<dayofweek>('
+    r'mo(n(day)?)?'
+    r'|tu(e(s(day)?)?)?'
+    r'|we(d(s|(nes(day)?)?)?)?|th(u(rs(day)?)?)?'
+    r'|fr(i(day)?)?'
+    r'|sa(t(urday)?)?'
+    r'|su(n(day)?)?'
+    r')))'
+)
 
 # A single cycle recurrence is one of:
 # - daily, weekly, monthly, yearly