Fenced code blocks inside indented code blocks

In fairly rare circumstances you may want to show the fences of a fenced code block. Normally this could be accomplished in Markdown by indenting the fenced code, forcing an indented "verbatim" block containing the fenced code block, which would then be unprocessed. Marked handles fenced code differently (as part of its ability to work with multiple syntax options), so to accomplish this you need to use a double fence. Because you can use any number of backticks or tildes to fence a code block (as long as the opening and closing count match, you can just use two different length fences. For example

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Actual fenced code
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