["html", ["p", "This is code (4 spaces):"],
    ["pre", ["code", "Code"]],
    ["p", "This is not code"],
    ["pre", ["code", "Code"]],
    ["p", "This is code (1 tab):"],
    ["pre", ["code", "Code"]],
    ["p", "This is not code"],
    ["pre", ["code", "Code"]]]
