Unable to inspect Celery Queue

I have become unable to use the inspect() function within Celery to see the active and reserved items within the queue. Instead of returning something like {u'celery@mymachine': []} it always returns None.

This began after I changed my Docker from using python:3.6-alpine to python:3.6, but now, even after I reverted back to alpine I still receive this behaviour. I have tried everything suggested here: Celery scheduled list returns None but none of it seems to work either.

I have included a minimal example below that shows my issue

If anyone has any ideas what may be causing this I would be very grateful

DockerFile:

FROM python:3.6-alpine
ENV CELERY_BROKER_URL redis://redis:6379/0
ENV CELERY_RESULT_BACKEND redis://redis:6379/0
ENV C_FORCE_ROOT true
WORKDIR /usr/src/app
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
COPY . .
CMD celery -A celeryExample worker --concurrency=1 --loglevel=info 

Docker-compose:

version: '3'

services:
  redis:
    image: redis
    ports:
      - 6379:6379
  celery: 
    build: 
        context: .
        dockerfile: Dockerfile.celery
    depends_on:
      - redis
    volumes: 
        - .:/usr/src/app    

requirements.txt

celery

celeryExample.py

from celery import Celery
import celeryconfig

broker_url = os.environ.get('broker_url', 'redis://localhost:6379/0'),
result_backend = os.environ.get('result_backend', 'redis://localhost:6379/0')

app = Celery('server', broker = broker_url,
                       backend = result_backend)
app.config_from_object(celeryconfig)

@app.task
def add(x, y):
    return x + y

celeryconfig:

worker_prefetch_multiplier = 1
worker_concurrency  = 1

active.py:

from celery import Celery
import celeryconfig
from celery.task.control import inspect
import os

broker_url = os.environ.get('broker_url', 'redis://localhost:6379/0'),
result_backend = os.environ.get('result_backend', 'redis://localhost:6379/0')

app = Celery('server', broker = broker_url,
                       backend = result_backend)
app.config_from_object(celeryconfig)

i = inspect()
q = i.active()
print(q)