**//NOTE: This endpoint is deprecated. If there are no callers, we may not need to implement it. We should confirm whether or not this endpoint is needed before working on it.Although this endpoint is deprecated, If the endpoint is not needed,it is still being called. we can close this task as InvalidWe therefore need to create a REST implementation for it according to its current contract (including the deprecated "id" value in the response).//**
**//NOTE: If we do need to keep this endpoint, we should see if we can at least remove the "id" value from the response//**
Create a REST handler and any other necessary associated code (extension.json entry, helper classes, etc.) for the `POST lists` endpoint.
[] endpoint implemented
[] tests created
[] tests pass
**Endpoint summary:**
Create a new list for the current user.
**Endpoint description:**
Creates a new empty list. On name conflict, does nothing and returns the data of an existing list.
Request must be authenticated with a MediaWiki session cookie.
Stability: [unstable](https://www.mediawiki.org/wiki/API_versioning#Unstable)
This endpoint is deprecated and might be removed without warning. Use the batch version instead.
**Associated RESTBase code**
[[ https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/services/restbase/+/d544e9da48b9c79afb2338b7bab6960a94db6c61/v1/lists.yaml#203 | lists.yaml ]] (spec+forwarding)
[[ https://gerrit.wikimedia.org/g/mediawiki/services/restbase/+/d544e9da48b9c79afb2338b7bab6960a94db6c61/test/features/lists.js#321 | lists.js ]] (tests)
**Associated Action API code**
[[ https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/ReadingLists/+/refs/heads/master/src/Api/ApiReadingListsCreate.php#13 | ApiReadingListsCreate ]]
[[ https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/ReadingLists/+/refs/heads/master/tests/phpunit/Api/ApiReadingListsCreateTest.php#16 | ApiReadingListsCreateTest ]]
**Parameters:**
| name | source | required | type | example | default | possible values | description |
| csrf_token | query | yes | string | f63c343876da566045e6b59c4532450559c828d3+\\ | N/A | N/A | The CRSF edit token provided by the MediaWiki API |
**Request Body:**
[[ https://gerrit.wikimedia.org/g/mediawiki/services/restbase/+/d544e9da48b9c79afb2338b7bab6960a94db6c61/v1/lists.yaml#932 | list_write ]]
**Error Response**
#/components/schemas/problem per [[ https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/services/restbase/+/refs/heads/master/doc/API.md | API.md ]] and [[ https://datatracker.ietf.org/doc/html/draft-nottingham-http-problem | draft-nottingham-http-problem ]]
**Success Response**
| value | type | description |
| id | integer | List ID. Deprecated, will be removed. Use the full list object. |
| list | object: [[ https://gerrit.wikimedia.org/g/mediawiki/services/restbase/+/d544e9da48b9c79afb2338b7bab6960a94db6c61/v1/lists.yaml#911 | list_read ]] | |
**Response Headers**
This endpoints has [[ https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/services/restbase/+/refs/heads/master/v1/lists.yaml#266 | additional response headers ]] specified in the RESTBase code:
```
headers:
content-type: application/json; charset=utf-8
```