upquote { upright-quote and grave-accent glyphs in verbatim
Michael A. Covington, Frank G. Mittelbach, Markus Kuhn · 2012
By default, the L ATEX \\verb macro and verbatim environment display ASCII characters 27 and 60 as ’ and ‘, respectively, in line with how these two characters are used to typeset opening and closing quotation marks elsewhere in TEX. However, the character-set standards define character 27 to represent a straight