diff --git a/utils.py b/utils.py
index 4a784ec..2e26207 100644
--- a/utils.py
+++ b/utils.py
@@ -111,5 +111,4 @@
             return int(ssize[:-1]) * SMAP[ssize[-1]]
         return int(ssize)
     except (ValueError, TypeError, AttributeError):
-        tmpl = "Unknow size format {0!r} (or size not multiples 1024)"
-        raise ValueError(tmpl.format(ssize))
+        raise ValueError("Unknow size format {0!r}".format(ssize))