goal in python

goal.py

def g(letters=None):
    if letters: return 'gal'
    goal = ['go']
    def o(letters=None):
        assert letters is None or letters == 'al'
        if letters:
            goal.append(letters)
            return ''.join(goal)
        goal.append('o')
        return o
    return o

if __name__ == '__main__':
    print(g('al'))
    print(g()('al'))
    print(g()()('al'))
    print(g()()()()()('al'))

goal_functional.py

from functools import partial
def f(times, letters=None):
    if letters:
        return 'g'+('o'*times)+letters
    return partial(f, times+1)
g=partial(f, 0)

if __name__ == '__main__':
    print(g('al'))
    print(g()('al'))
    print(g()()('al'))
    print(g()()()()()('al'))