^^A  Color-code metadata values.
\newcommand{\metavalue}[1]{\textcolor{blue}{#1}}

^^A  Define today's today in ISO format.
\makeatletter
\edef\todayISO{\the\year-}
\ifnum\month<10\relax
  \g@addto@macro\todayISO{0}
\fi
\g@addto@macro\todayISO{\the\month-}
\ifnum\day<10\relax
  \g@addto@macro\todayISO{0}
\fi
\g@addto@macro\todayISO{\the\day}
\makeatother

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