1 files changed, 2 insertions, 2 deletions

diff --git a/MAT/parser.py b/MAT/parser.py
index e956164..949e24b 100644
--- a/MAT/parser.py
+++ b/MAT/parser.py
@@ -11,12 +11,12 @@ import shutil
 
 import mat
 
-NOMETA = ('.bmp',  # image
+NOMETA = frozenset(('.bmp',  # image
           '.rdf',  # text
           '.txt',  # plain text
           '.xml',  # formated text (XML)
           '.rels',  # openXML formated text
-          )
+          ))
 
 FIELD = object()