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I have docker compose file set up as shown below:

version: '3.7'

services:
  reverse-proxy:
    image: traefik:2.6
    hostname: "traefik"
    command:
      - "--api.dashboard=true"
      - "--providers.docker"
      - "--providers.docker.swarmMode=true"
      - "--entrypoints.web.address=:80"
      - "--providers.docker.exposedByDefault=false"
      - "--providers.docker.network=web"
      - "--log.level=DEBUG"
      - "--log.filePath=/var/log/traefik.log"
      - "--accessLog.filePath=/var/log/access.log"
    ports:
      - "80:80"
      - "8080:8080"

    volumes:
      - /etc/localtime:/etc/localtime:ro
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - /var/log/traefik.log:/var/log/traefik.log
      - /var/log/access.log:/var/log/access.log
      - /home/ansible/stacks/traefik/static/traefik.yml:/traefik.yml
      - /home/ansible/stacks/traefik/config:/config/
    networks:
      - web
    deploy:
      labels:
          - "diun.enable=true"
          - "traefik.enable=true"
          - "traefik.http.routers.api.rule=Host(`traefik.home.local`)"
          - "traefik.http.routers.api.service=api@internal"
          # - "traefik.http.routers.api.middlewares=auth"
          # - "traefik.http.middlewares.auth.basicauth.users="
          # Dummy service for Swarm port detection. The port can be any valid integer value.
          - "traefik.http.services.dummy-svc.loadbalancer.server.port=9999"
      mode: global
      placement:
        constraints: [node.role == manager]

networks:
  proxy:
    driver: bridge
    external: true

networks:
  web:
    name: web

but this errors:

failed to create network web: Error response from daemon: network with name web already exists

what I dont understand is last network definition trying to create the network web ? or making it available to use ?