diff --git a/i3pystatus/mem.py b/i3pystatus/mem.py
index a1a77d2..9e26ea2 100644
--- a/i3pystatus/mem.py
+++ b/i3pystatus/mem.py
@@ -44,7 +44,7 @@ class Mem(IntervalModule):
     def run(self):
         memory_usage = psutil.virtual_memory()
 
-        if psutil.version_info < (4,4,0):
+        if psutil.version_info < (4, 4, 0):
             used = memory_usage.used - memory_usage.cached - memory_usage.buffers
         else:
             used = memory_usage.used