Merge pull request #42 from farshidce/issue41-fix

fix-#41 : lazy_format __str__ function should return the formatted string

python_jsonschema_objects/util.py

@@ -12,7 +12,7 @@ def __init__(self, fmt, *args, **kwargs):
         self.kwargs = kwargs
 
     def __str__(self):
-        self.fmt.format(*self.args, **self.kwargs)
+        return self.fmt.format(*self.args, **self.kwargs)
 
 
 def safe_issubclass(x, y):