Double Superscript

\documentclass{scrartcl}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{amsmath}

\usepackage{breqn}

\begin{document}
\begin{align*}
\pi'^{,*}
\end{align*}
\end{document}