I am using Option parser for creating a command line application .
I am able to parse command line options.
I have a command for listing the contents of a folder.
which goes like this
python main.py --listContents
When I give this I get an error
error: --listContents option requires an argument
when I give the same command with
python main.py --listContents xxxx
it runs fine no matter what value is xxxx
Why does not it work without xxxx?