/usr/share/php/Symfony/Component/Cache/Traits/ is in php-symfony-cache 3.4.6+dfsg-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/php/Symfony/Component/Cache/Traits/AbstractTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/ApcuTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/ArrayTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/DoctrineTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/FilesystemCommonTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/FilesystemTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/MemcachedTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/PdoTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/PhpArrayTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/PhpFilesTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/ProxyTrait.php
/usr/share/php/Symfony/Component/Cache/Traits/RedisProxy.php
/usr/share/php/Symfony/Component/Cache/Traits/RedisTrait.php