diff --git a/src/utils/time.py b/src/utils/time.py
index 0dcbb3b27..542e50019 100644
--- a/src/utils/time.py
+++ b/src/utils/time.py
@@ -41,7 +41,7 @@ try:
 except ImportError:
     pytz = None
 
-_IANA_TZ_RE = re.compile("([\w_-]+/)*[\w_-]+")
+_IANA_TZ_RE = re.compile(r"([\w_-]+/)*[\w_-]+")
 
 class TimezoneException(Exception):
     pass