s.capitalize() s.center(width) s.count(sub [,start [,end]]) s.find(sub [,start [,end]]) s.isalnum() s.join(t) s.lower() s.replace(old,new [,maxreplace]) ...
s = "Hello World" t = s.upper() # t = "HELLO WORLD" a = s.split() # a = ['Hello', 'World']