Use betterhelp's easy main to get parser off the global.

pixelcanvas.py

@@ -550,6 +550,7 @@ def update_argparse(args):
     except KeyboardInterrupt:
         sql.commit()
 
+def main(argv):
     parser = argparse.ArgumentParser()
     subparsers = parser.add_subparsers()
 
@@ -571,10 +572,12 @@ p_render.set_defaults(func=render_argparse)
     p_overview = subparsers.add_parser('overview')
     p_overview.set_defaults(func=overview_argparse)
 
-@betterhelp.subparser_betterhelp(parser, main_docstring=DOCSTRING, sub_docstrings=SUB_DOCSTRINGS)
-def main(argv):
-    args = parser.parse_args(argv)
-    return args.func(args)
+    return betterhelp.subparser_main(
+        argv,
+        parser,
+        main_docstring=DOCSTRING,
+        sub_docstrings=SUB_DOCSTRINGS,
+    )
 
 if __name__ == '__main__':
     raise SystemExit(main(sys.argv[1:]))