app.py

from core.extensions import celery

app = Flask(__name__)
celery.init_app(app)

app.run()

extensions.py

class CeleryHelper():
    def init_app(self, app):
        # Do stuff
        self.celery = celery
        
    def __getattr__(self, name):
        return getattr(self.celery, name)
        
        
celery = CeleryHelper()

task.py

from core.extension import celery

@celery.task
def stuff():
   # do stuff