diff --git a/README.md b/README.md
index aeb3032..b349cf3 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ Usage
 - Converter hyperbola-bootstrap to bootstrap image valid for docker
 
     ```console
-    $ ./tar_fix.py --input=hyperbola-bootstrap.tar.gz --output=bootstrap.tar.gz
+    $ python3 tar_fix.py --input=hyperbola-bootstrap.tar.gz --output=bootstrap.tar.gz
     ```
 
 - Make sure you have my `Dockerfile`, `.dockerignore` and the `bootstrap.tar.gz` in one directory.
diff --git a/tar_fix.py b/tar_fix.py
old mode 100755
new mode 100644