Update tools.py

If you don't use the condition expression speed may be 0 initially

deep-person-reid-master\torchreid\utils\tools.py", line 86, in _reporthook
    speed = int(progress_size / (1024*duration))
ZeroDivisionError: float division by zero

torchreid/utils/tools.py

@@ -83,7 +83,7 @@ def _reporthook(count, block_size, total_size):
             return
         duration = time.time() - start_time
         progress_size = int(count * block_size)
-        speed = int(progress_size / (1024*duration))
+        speed = 0 if duration == 0 else int(progress_size / (1024*duration))
         percent = int(count * block_size * 100 / total_size)
         sys.stdout.write(
             '\r...%d%%, %d MB, %d KB/s, %d seconds passed' %