/usr/share/doc/readseq/tests/alphabet.std is in readseq 1-11.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | >alphabet['!'..'~'], 83 bases, 9429 checksum.
!"#$%&'()*+-./:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]
^_`abcdefghijklmnopqrstuvwxyz{|}~
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