Remove cli function

day2/day2_sample.py

@@ -92,10 +92,5 @@ def main(argv=None):
     return count_safe_in_file(args.input)
 
 
-def cli(argv=None):
-    print(main(argv))
-    return 0
-
-
 if __name__ == "__main__":
-    raise SystemExit(cli())
+    print(main())