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##### SUMMARY
<!--- Explain the problem briefly below -->
The [docker_container](https://docs.ansible.com/ansible/latest/modules/docker_container_module.html) module recreates a container when the `restart_policy` is changed. This can be changed using the `docker update` command.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
[docker_container](https://docs.ansible.com/ansible/latest/modules/docker_container_module.html)

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```shell
$ ansible --version
ansible 2.9.2
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/ingmar/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.5 (default, Oct 17 2019, 12:09:47) [GCC 9.2.1 20190827 (Red Hat 9.2.1-1)]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below
$ ansible-config dump --only-changed
<empty>
```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->
```shell
$ lsb_release -a
LSB Version:    :core-4.1-amd64:core-4.1-noarch
Distributor ID: Fedora
Description:    Fedora release 30 (Thirty)
Release:        30
Codename:       Thirty
```

##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->
1. Run the following playbook:
```sh
$ ansible-playbook docker-container-update.yml
```
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: Container update restart_policy
  hosts: localhost
  tasks:
    - name: Container with restart_policy
      docker_container:
        name: restart_policy_example
        image: alpine
        state: present
        restart_policy: unless-stopped
        entrypoint: top
```
2. Change the `restart_policy` to `always` and run it again.
```sh
$ ansible-playbook docker-container-update.yml
```
<!--- Paste example playbooks or commands between quotes below -->
```yaml
- name: Container update restart_policy
  hosts: localhost
  tasks:
    - name: Container with restart_policy
      docker_container:
        name: restart_policy_example
        image: alpine
        state: present
        restart_policy: unless-stopped
        entrypoint: top
```
3. Notice by using the `docker ps` command that the container is recreated instead of updated.

##### EXPECTED RESULTS
I expect the container to be update with  the new `restart_policy` by using the docker update command:
```sh
$ docker update --restart=<new policy>
``` 

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->
The container is recreated instead of updated.
I currently run a `command` task before the container which updates the command.
```yml
# Update docker restart policy
- name: Update docker container restart policy
  command: "docker update --restart={{ (restart_policy == false) | ternary('no', restart_policy) }} {{ container }}"
  ignore_errors: true
```
option has a default of C(no).
    type: bool
  recreate:
    description:
      - Use with present and started states to force the re-creation of an existing container.
    type: bool
    default: no
  removal_wait_timeout:
    description:
      - When removing an existing container, the docker daemon API call exists after the container
        is scheduled for removal. Removal usually is very fast, but it can happen that during high I/O
        load, removal can take longer. By default, the module will wait until the container has been
        removed before trying to (re-)create it, however long this takes.
      - By setting this option, the module will wait at most this many seconds for the container to be
        removed. If the container is still in the removal phase after this many seconds, the module will
        fail.
    type: float
    version_added: "2.10"
  restart:
    description:
      - Use with started state to force a matching container to be stopped and restarted.
    type: bool
    default: no
  restart_policy:
    description:
      - Container restart policy.
      - Place quotes around C(no) option.
    type: str
    choices:
      - 'no'