diff --git a/demo_copy.py b/demo_copy.py
index ec78f3e..548af76 100644
--- a/demo_copy.py
+++ b/demo_copy.py
@@ -12,6 +12,11 @@
 """
 from docopt import docopt
 opt = docopt(__doc__)
-print(opt['<arg4>'])
-print(opt)
-print(type(opt))
+
+def main():
+    print(opt['<arg4>'])
+    print(opt)
+    print(type(opt))
+    
+if __name__ == "__main__":
+    main()