uncnf.py

import re
from sys import stdin

def uncnf(g):
    return type(g) not in (list, tuple) and g or map(uncnf, g[g[0]=='<DEL>':])

for line in stdin:
    line = re.sub(' +', ',', re.sub('([^() ]+)', r"'\1'", re.sub('([()])', r' \1 ', line).strip()))
    line = eval(re.sub(r'\[X[1-9][0-9]*\]', '<DEL>', line.replace('(,', '(')))
    print uncnf(line)