documentclass[11pt]{amsart}
title{test}
author{Aleksandr Kozlovskiy}
date{today}
thanks{This document  was printted in LaTex by Aleksandr Kozlovskiy from minsk.}
makeatletter
defmaketitle{
textbf{@title}
textit{@author}
text{@thanks}
}
makeatother
begin{document}
maketitle
this is a test document
end{document}