[tools/dict_parser] Reader: is_valid_attribute err

Adding the error / warning methods call to the DictReader
is_valid_attribute handling.

Author: mpsonntag

odml/tools/dict_parser.py

@@ -202,7 +202,10 @@ def is_valid_attribute(self, attr, fmt):
         if fmt.revmap(attr):
             return attr
 
-        msg = "Invalid element <%s> inside <%s> tag" % (attr, fmt.__class__.__name__)
+        msg = "Invalid element |%s| inside <%s> tag" % (attr, fmt.__class__.__name__)
+        self.error(msg)
+
+        return None
 
     def error(self, msg):
         """
@@ -228,11 +231,10 @@ def warn(self, msg):
         msg = "warning: %s\n" % msg
 
         self.warnings.append(msg)
+
         if self.show_warnings:
             print(msg)
 
-        return None
-
     def to_odml(self, parsed_doc):
         """
         Parses a Python dictionary object containing an odML document to an odml.Document.