I need to convert this iterative code on Python into a recursive code.

RESTRICTIONS: No lists, No modules are allowed to be imported.

The Question is that in a string, i have to remove non alphabetic characters such as numbers, symbols and whitespaces.

" 67&* bbbc&" should give "bbbc"

ITERATION CODE:

def remove_nonalpha(string): s = "" for i in string: if i.isalpha() == True: s = s + i return s