Python Celery试图在docker-compose中占用端口号并造成问题

docker-compose.yml：

  python-api: &python-api
    build:
      context: /Users/AjayB/Desktop/python-api/
    ports:
      - "8000:8000"
    networks:
      - app-tier
    expose:
      - "8000"
    depends_on:
      - python-model
    volumes:
      - .:/python_api/
    environment:
      - PYTHON_API_ENV=development
    command: >
      sh -c "ls /python-api/ &&
             python_api_setup.sh development
             python manage.py migrate &&
             python manage.py runserver 0.0.0.0:8000"

  python-model: &python-model
    build:
      context: /Users/AjayB/Desktop/Python/python/
    ports:
      - "8001:8001"
    networks:
      - app-tier
    environment:
      - PYTHON_API_ENV=development
    expose:
      - "8001"
    volumes:
      - .:/python_model/
    command: >
      sh -c "ls /python-model/
             python_setup.sh development
             cd /server/ &&
             python manage.py migrate &&
             python manage.py runserver 0.0.0.0:8001"

  python-celery:
    <<: *python-api
    environment:
      - PYTHON_API_ENV=development
    networks:
      - app-tier
    links:
      - redis:redis
    depends_on:
      - redis
    command: >
      sh -c "celery -A server worker -l info"

  redis:
    image: redis:5.0.8-alpine
    hostname: redis
    networks:
          - app-tier
    expose:
      - "6379"
    ports:
      - "6379:6379"
    command: ["redis-server"]

python-celery在python-api其中应作为单独的容器运行。但是，它试图占用与相同的端口python-api，这绝对不可能。

我得到的错误是：

AjayB$ docker-compose up
Creating integrated_redis_1        ... done
Creating integrated_python-model_1 ... done
Creating integrated_python-api_1   ... 
Creating integrated_python-celery_1 ... error

Creating integrated_python-api_1    ... done
e1d1055165b1f85f179f69c): Bind for 0.0.0.0:8000 failed: port is already allocated

ERROR: for python-celery  Cannot start service python-celery: driver failed programming external connectivity on endpoint integrated_python-celery_1 (ab5e079dbc3a30223e16052f21744c2b5dfc56adbe1d1055165b1f85f179f69c): Bind for 0.0.0.0:8000 failed: port is already allocated
ERROR: Encountered errors while bringing up the project.

在做docker ps -a，我得到这个：

AjayB$ docker ps -a
CONTAINER ID        IMAGE                      COMMAND                  CREATED             STATUS                      PORTS                    NAMES
2ff1277fb7a7        integrated_python-celery   "sh -c 'celery -A se…"   10 seconds ago      Created                                              integrated_python-celery_1
5b60221b42a4        integrated_python-api      "sh -c 'ls /crackd-a…"   11 seconds ago      Up 9 seconds                0.0.0.0:8000->8000/tcp   integrated_python-api_1
bacd8aa3268f        integrated_python-model    "sh -c 'ls /crackd-m…"   12 seconds ago      Exited (2) 10 seconds ago                            integrated_python-model_1
9fdab833b436        redis:5.0.8-alpine         "docker-entrypoint.s…"   12 seconds ago      Up 10 seconds               0.0.0.0:6379->6379/tcp   integrated_redis_1

尝试强行卸下容器，并尝试docker-compose up得到相同的错误。：/我在哪里犯错？只是怀疑volumes:部分。谁能告诉我是否volumes正确？并请帮助我解决此错误。PS，首先尝试使用docker。谢谢！