Pipe input for table content is working odd

Question

I have following document:

\documentclass[parskip=half-]{scrreprt}
\usepackage{ragged2e}
\usepackage{makecell,xltabular}
\usepackage[dvipsnames,x11names,table]{xcolor}
\begin{document}
\subsection{Test table}
\begin{xltabular}{\textwidth}{|>{\ttfamily\RaggedRight\arraybackslash}p{6.5cm}|>{\centering\arraybackslash}p{0.6cm}|m{1.8cm}|X|}
    \caption{Table caption}
    \label{tab:test-table}\
    \hline
    \rowcolor{gray}
    \thead{\textnormal{Col1}} & \thead{Col2} & \thead{Col3} & \thead{Col4}                                                                                                                                                                                                   \ \hline
    \endfirsthead
    %
    \multicolumn{4}{c}%
    {{\bfseries Table \thetable\ continued from previous page}} \
    \hline
    \rowcolor{gray}
    \thead{\textnormal{Col1}} & \thead{Col2} & \thead{Col3} & \thead{Col4}                                                                                                                                                                                                   \ \hline
    \endhead
    %

    \multicolumn{4}{|c|}{\cellcolor{lightgray}\textbf{Table section}} \ \hline
    1 & 2 & 3 & 4 \ \hline
    \input{|"./test.py"}
\end{xltabular}
\end{document}

I'm using an \input with pipe: \input{|"./test.py"}

If the content of the test.py is:

#!/usr/bin/env python3
print(r'\multicolumn{4}{|c|}{\cellcolor{lightgray}\textbf{Table section 2}} \ \hline')
print(r'11 & 22 & 33 & 44 \ \hline')

I get an error:

! Misplaced \omit.
\multispan ->\omit 
                   \@multispan 
l.1 ...llcolor{lightgray}\textbf{Table section 2}}
                                                   \\ \hline
!  ==> Fatal error occurred, no output PDF file produced!

If I swap two last lines in the python script, I don't get an error but the table has two extra vertical lines.

#!/usr/bin/env python3
print(r'11 & 22 & 33 & 44 \ \hline')
print(r'\multicolumn{4}{|c|}{\cellcolor{lightgray}\textbf{Table section 2}} \ \hline')

I generate pdf with: latexmk -shell-escape -enable-pipes -pdf -halt-on-error test.tex

What I'm doing wrong?