As long as the `external-id` data type does not exist, we will start with a basic setting like this:
```lang=php
$wgWBRepoSettings['statementSections'] = array(
'item' => array(
'statements' => null,
'identifiers' => array(
'type' => 'propertySet',
'propertyIds' => array(
'P61',
'…',
),
),
),
);
```
This is what this setting does:
* It's only active for items. Properties will not have sections in addition to the default "Statements".
* There will be a default "Statements" section for everything that does not fit to an other section.
* There will be an "Identifiers" section for specific property ids. The section heading message is https://translatewiki.net/wiki/MediaWiki:Wikibase-statementsection-identifiers/en.
Later, when the `external-id` data type finally exists, the setting will be changed:
```lang=php
$wgWBRepoSettings['statementSections'] = array(
'item' => array(
'statements' => null,
'identifiers' => array(
'type' => 'dataType',
'dataTypes' => array( 'external-id' ),
),
),
);
```