可能有点超出我的深度，我已经彻底阅读了heroku文档，但仍然不太明白Procfile应该如何设置。尝试部署 heroku ( $ heroku open)，给出以下错误日志：
2020-01-27T11:39:57.597570+00:00 app[web.1]: backlog: 2048\n2020-01-27T11:39:57.597572+00:00 app[web.1]: workers: 1\n2020-01-27T11:39:57.597590+00:00 app[web.1]: worker_class: sync\n2020-01-27T11:39:57.597592+00:00 app[web.1]: threads: 1\n2020-01-27T11:39:57.597594+00:00 app[web.1]: worker_connections: 1000\n2020-01-27T11:39:57.597596+00:00 app[web.1]: max_requests: 0\n2020-01-27T11:39:57.597598+00:00 app[web.1]: max_requests_jitter: 0\n2020-01-27T11:39:57.597600+00:00 app[web.1]: timeout: 30\n2020-01-27T11:39:57.597602+00:00 app[web.1]: graceful_timeout: 30\n2020-01-27T11:39:57.597604+00:00 app[web.1]: keepalive: 2\n2020-01-27T11:39:57.597606+00:00 app[web.1]: limit_request_line: 4094\n2020-01-27T11:39:57.597608+00:00 app[web.1]: limit_request_fields: 100\n2020-01-27T11:39:57.597610+00:00 app[web.1]: limit_request_field_size: 8190\n2020-01-27T11:39:57.597612+00:00 app[web.1]: reload: False\n2020-01-27T11:39:57.597614+00:00 app[web.1]: reload_engine: auto\n2020-01-27T11:39:57.597615+00:00 app[web.1]: spew: False\n2020-01-27T11:39:57.597617+00:00 app[web.1]: check_config: False\n2020-01-27T11:39:57.597619+00:00 app[web.1]: preload_app: True\n2020-01-27T11:39:57.597621+00:00 app[web.1]: sendfile: None\n2020-01-27T11:39:57.597623+00:00 app[web.1]: chdir: /app\n2020-01-27T11:39:57.597625+00:00 app[web.1]: daemon: False\n2020-01-27T11:39:57.597627+00:00 app[web.1]: raw_env: []\n2020-01-27T11:39:57.597629+00:00 app[web.1]: pidfile: None\n2020-01-27T11:39:57.597630+00:00 app[web.1]: worker_tmp_dir: …