[Tex/LaTex] Nested itemize in beamer with different bullet shape, font size

Question

I found the following code here which changes the font size and bullet size for nested itemize. I just want to change the bullet shape as well, for example circle for subitem. But I cannot. I tried removing this code and use some other available for this, but I don't what the issue is, but wif I remove this code, all the bullets of my slide will gone (white space instead appears). Any idea for editing this code to meet my requirement?

\documentclass{beamer}
\usepackage{enumitem} 
\usepackage{wasysym}

\setlist[enumerate, 1]{label*=\arabic*., listparindent=21pt, font=\bfseries\tiny, before*=\footnotesize }

\setlist[itemize,1]{before*=\small}
\setlist[itemize,2]{before*=\footnotesize}

\setbeamertemplate{itemize item}[square]

\setitemize{label=\usebeamerfont*{itemize item} \usebeamercolor[fg]{itemize item} \usebeamertemplate{itemize item}}

Answer 1

Instead of trying to use enumitem with beamer, I'd stick with beamer's own mechanism.

\documentclass{beamer}

\setbeamertemplate{itemize item}[square]
\setbeamertemplate{itemize subitem}[circle]

\setbeamerfont{itemize/enumerate subbody}{size=\scriptsize}

\begin{document}

\begin{frame}

    \begin{itemize}
        \item An item
        \begin{itemize}
        \item a subitem
        \end{itemize}
    \end{itemize}

\end{frame} 

\end{document}