import json
import base64
import random


def base64url_decode(base64_str):
    size = len(base64_str) % 4
    if size == 2:
        base64_str += '=='
    elif size == 3:
        base64_str += '='
    elif size != 0:
        raise ValueError('Invalid base64 string')
    return base64.urlsafe_b64decode(base64_str.encode('utf-8'))


def parse_jwt(jwt_token):
    jwt_token_list = jwt_token.split('.')
    header = base64url_decode(jwt_token_list[0]).decode()
    payload = base64url_decode(jwt_token_list[1]).decode()
    return {
        'header': json.loads(header),
        'payload': json.loads(payload),
        'signature': jwt_token_list[-1]
    }

def generate_random_code(n):
    range_start = 10**(n-1)
    range_end = (10**n)-1
    return str(random.randint(range_start, range_end))