import random
import string


def generate_captcha(request):
    code = ''.join(random.choices(string.ascii_uppercase + string.digits, k=5))
    request.session['captcha_code'] = code
    return code


def validate_captcha(request, value):
    stored = request.session.get('captcha_code') or ''
    request.session['captcha_code'] = None
    return stored and value and str(value).strip() == str(stored).strip()