\documentclass{article}
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\begin{document}
With the user changed label commands, the standard labels occure now
in the following form:
\begin{itemize}
\item The label for the first level is a long dash (em dash).
\begin{itemize}
\item That for the second level a medium dash (en dash).
\begin{itemize}
\item And that for the third level a short dash, a hyphen.
\item Changed label symbols should be uniform for the whole users documen.
\end{itemize}
\item Also not changed several times within the document.
\end{itemize}
\item As shown here.
\end{itemize}
\end{document}

