diff --git a/main.tex b/main.tex
index 43aba37..38d1ea4 100644
--- a/main.tex
+++ b/main.tex
@@ -23,7 +23,6 @@
 \usepackage{tocloft}                % control over the typography of the Table of Contents, etc.
 \usepackage{listings}               % code listings
 \usepackage{color}                  % more colors
-\usepackage{tikz}                   % painting
 \usepackage{tikz-imagelabels}       % overlay labels for images
 \usepackage{cite}                   % citation for bibliography
 \usepackage{amssymb}                % provides enhancements for mathematical formulas
@@ -83,7 +82,10 @@
     % include all used chapters
     \input{config/chapter.tex}
 
-
+    \begin{minted}{python3}
+        if __name__ != "main":
+            exit(1)
+    \end{minted}
 
     % source references follow content of article
     \input{pages/page-09-bibliography}