This script sorts a directory full of torrents into subdirectories per tracker.

sort_torrents.py

#!/usr/bin/env python3.5

import os
from urllib.parse import urlparse

def read_header(h):
    assert(h[:11] == b'd8:announce')
    ann_head_end = h.index(b':',11)
    announce_length = int(h[11:ann_head_end])
    announce_start = ann_head_end + 1
    announce_end = announce_start + announce_length
    announce = h[announce_start:announce_end]
    return announce.decode('utf8')
    
def get_tracker(f):
    with(open(f, "rb")) as fh:
        header = fh.read(1024)
    announce = read_header(header)
    tracker = urlparse(announce).netloc.split(':')[0]
    return tracker

for f in os.scandir('.'):
    if f.is_file() and '.torrent' in f.name:
        tracker = get_tracker(f.name)
        os.makedirs(tracker, exist_ok=True)
        dst = os.path.join(tracker, f.name)
        os.rename(f.name, dst)