This sentence employs two a’s, two c’s, two d’s, twenty-eight e’s, five f’s, three g’s, eight h’s, eleven i’s, three l’s, two m’s, thirteen n’s, nine o’s, two p’s, five r’s, twenty-five s’s, twenty-three t’s, six v’s, ten w’s, two x’s, five y’s, and one z.
Such sentences are called autograms. Your task is to write a program or function that has a similar property: it takes as input a byte, and outputs an integer representing the number of times that byte appears in the program's source code. It should output 0 if its input doesn't appear in its source.
Your program must not read its own source code, directly or indirectly, but instead all the data it needs to give its output must be hard-coded, quine style. Your program must be at least one byte in length.
This is code-golf, so the shortest entry (in bytes) wins. I won't accept an answer, so feel free to compete for the shortest solution in your favourite language.
You are strongly encouraged to include an explanation in your post.
Leaderboards
Below are leaderboards both for overall score and per language:
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