\newcommand{\ErrorTok}[1]{\textcolor[rgb]{1.00,0.00,0.00}{\textbf{#1}}}
\newcommand{\NormalTok}[1]{#1}
+% these come from:
+% https://gist.github.com/bgeron/72ebbacf5930537022079d9953f15713
+\usepackage{newunicodechar}
+\newcommand\DeclareUnicodeInv[2]{\DeclareUnicodeCharacter{#2}{#1}}
+
+\DeclareUnicodeCharacter{03A0}{\ensuremath{\Pi}}
+\DeclareUnicodeCharacter{2208}{\ensuremath{\in}}
+\DeclareUnicodeCharacter{03C0}{\ensuremath{\pi}}
+\DeclareUnicodeCharacter{221A}{$\sqrt{}$}
+\DeclareUnicodeCharacter{221B}{$\sqrt[3]{}$}
+\DeclareUnicodeInv{\ensuremath{\mathbb{Z}}}{2124}
+
% indent all verbatim
\catcode`\@=11
\let \saveverbatime \@xverbatim