\input should not be parsed when it's part of a verbatim environment (po4a::tex: Cannot find 'main.tex' with kpsewhich)

[Freed-Wu]

example.tex

\begin{verbatim}
\documentclass[ignorenonframetext]{beamer}
\input{main.tex}
\end{verbatim}

po4a-gettexttize will search main.tex by kpsewhich, however, it doesn't exist, so it failed.

In fact, it is hard to handle. must detect if \input is surrounded by verbatim, minted, lslsting ... So if there are something to allow user skip the non-exist file?