https://docs.python.org/2/library/argparse.html#invalid-arguments When it encounters such an error, it exits and prints the error along with

a usage message:

"It" in the sentence refers to the parse_args() method. Saying that "it exits" makes it sound as if the method exits. Rather, an error in parsing causes sys.exit() to be called, exiting the entire script. Suggested rewrite: When it encounters such an error, parse_args() prints the error and a usage

message, then causes the script to exit immediately. No exception is raised.

Whether it's worth noting that the exit is the result of sys.exit(), I can't say. I don't need that level of detail. -- *Michael Cowperthwaite* Sr. Software Engineer Accel Biotech LLC, a Ximedica company 103 Cooper Court, Los Gatos, CA 95032 408.354.1700 x <408.354.1700%20x%20307>559 www.accelbiotech.com Providence | Minneapolis | San Francisco | Los Gatos | Hong Kong Visit us at www.ximedica.com and read our blog, *Living Innovation. <http://www.ximedica.com/People/LivingInnovationBlog.aspx>* The information contained in this transmission may contain privileged and confidential information. It is intended only for the use of the person(s) named above and/or involved in the noted project(s). If you are not the intended recipient, you are hereby notified that any review, dissemination, distribution or duplication of this communication is strictly prohibited. If you are not the intended recipient, please contact the sender by reply email and destroy all copies of the original message.