$this->addOption( 'username-prefix', 'Prefix for interwiki usernames', false, true );
		$this->addOption( 'no-local-users',
			'Treat all usernames as interwiki. ' .
			'The default is to assign edits to local users where they exist.',
			false, false
		);

		if ( $this->hasOption( 'username-prefix' ) ) {
			$importer->setUsernamePrefix(
				$this->getOption( 'username-prefix' ),
				!$this->hasOption( 'no-local-users' )
			);
		}

	/**
	 * @since 1.31
	 * @param string $usernamePrefix Prefix to apply to unknown (and possibly also known) usernames
	 * @param bool $assignKnownUsers Whether to apply the prefix to usernames that exist locally
	 */
	public function setUsernamePrefix( $usernamePrefix, $assignKnownUsers ) {
		$this->externalUserNames = new ExternalUserNames( $usernamePrefix, $assignKnownUsers );
	}

		$this->externalUserNames = new ExternalUserNames( 'imported', false );

	/**
	 * @param string $usernamePrefix Prefix to apply to unknown (and possibly also known) usernames
	 * @param bool $assignKnownUsers Whether to apply the prefix to usernames that exist locally
	 */
	public function __construct( $usernamePrefix, $assignKnownUsers ) {
		$this->usernamePrefix = rtrim( (string)$usernamePrefix, ':>' );
		$this->assignKnownUsers = (bool)$assignKnownUsers;
	}

			// @phan-suppress-next-line PhanTypeMismatchArgumentNullable False positive
			$importer->setUsernamePrefix( $fullInterwikiPrefix, $assignKnownUsers );