diff --git a/beat/web/common/__init__.py b/beat/web/common/__init__.py
index d3a37534bbd57d0b41793eacbf5e6441afa3b1bd..da2fecd26f3e874ae13c7d37f7aa64c09a97199c 100644
--- a/beat/web/common/__init__.py
+++ b/beat/web/common/__init__.py
@@ -25,4 +25,6 @@
 #                                                                             #
 ###############################################################################
 
-is_true = lambda value: bool(value) and value.lower() not in ('false', '0')
+
+def is_true(value):
+    return bool(value) and value.lower() not in ["false", "0"]