<http://schema.org/description>
"\u7B2C\u4E00\u6B21\u770B\u5230\u5F39\u5E55\u8FD9\u4E48\u5C11\u7684free(\uFF9F\u0414\uFF9F\u2261\uFF9F\u0414\uFF9F)"^^<http://www.w3.org/2001/XMLSchema#string>
<https://catfan.me/piggsy/p256835>