Python Functions Error in Pyton Script node

I am attempting to use built in python functions like isdigit(), rsplit() and more but none of them are defined in the python script node? How can I fix this so I can utilize python to its full ability within knime. Sorry if this is a basic question, I am a new user of knime.
Thanks for the help!

Hi @khyledhanani ,

are you sure that isdigit isn’t used as a method on the string x as follows:

	if x.isdigit():
		lis += x
		lis += ' '

(and welcome to the KNIME community! )