\documentclass[12pt]{article}

%\usepackage{theorem,amsmath,amssymb,russcorr}
\usepackage{amsthm,amsmath,amssymb}
\usepackage{color}
\usepackage[koi8-r]{inputenc}
\usepackage[russianb]{babel}

\long\def\comment#1\endcomment{}

\pagestyle{empty}

%\input{listki.tex}

\begin{document}

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\end{picture}
\end{center}

\end{document}