TypeError: 'Flask' object is not iterable

[abuvanth]

ewall-desk-05@ewalldesk-05:~/openprocurement.auction/openprocurement/auction$ gunicorn auctions_server:make_auctions_app
[2017-10-20 18:21:34 +0000] [3533] [INFO] Starting gunicorn 19.7.1
[2017-10-20 18:21:34 +0000] [3533] [INFO] Listening at: http://127.0.0.1:8000 (3533)
[2017-10-20 18:21:34 +0000] [3533] [INFO] Using worker: sync
[2017-10-20 18:21:34 +0000] [3538] [INFO] Booting worker with pid: 3538
[2017-10-20 18:21:35 +0000] [3538] [ERROR] Error handling request /favicon.ico
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/gunicorn/workers/sync.py", line 135, in handle
self.handle_request(listener, req, client, addr)
File "/usr/local/lib/python2.7/dist-packages/gunicorn/workers/sync.py", line 182, in handle_request
for item in respiter:
TypeError: 'Flask' object is not iterable
[2017-10-20 18:22:06 +0000] [3533] [CRITICAL] WORKER TIMEOUT (pid:3538)
[2017-10-20 18:22:06 +0000] [3538] [INFO] Worker exiting (pid: 3538)
[2017-10-20 18:22:06 +0000] [3548] [INFO] Booting worker with pid: 3548