If I want to remove the default set of 'whitespace' characters plus something else from a string there's currently no way to cleanly specify that.  In addition there's no way to programatically acquire what characters are considered whitespace so you can't call split with an argument constructed of existing whitespace characters with the new things you need.

As an example you could have an additionally= parameter such that:

"   ( 123 )   ".strip() gives "( 123 )" and
"   ( 123 )   ".strip(additionally="()") gives "123"

I've not given that any thought so it's probably not the best way of solving the problem.