how to define inparaenum in the preamble

Question

I'm using both \inparaenum and \enumerate in my thesis and I would like them to set them in the preamble so that each item is set off with a). I used

\setenumerate[0]{\itshape a\upshape)}

in the preamble for \enumerate but I don't know what to do for \inparaenum. I tried

\renewcommand{\begin{inparaenum}}{\begin{inparaenum}[\itshape a\upshape)]}

and I tried

\setinparaenum[0]{\itshpae a\upshape)}

and neither worked. Probably those attempts make people cringe, so sorry.

MWE:

\documentclass[11pt]{amsart}
\usepackage{paralist}
\usepackage[shortlabels]{enumitem}

\begin{document}

\setenumerate[0]{\itshape a\upshape)}
%\renewcommand{\begin{inparaenum}}{\begin{inparaenum}[\itshape a\upshape)]}
%\setinparaenum[0]{\itshpae a\upshape)}

This is a list:
\begin{enumerate}
\item item one
\item item two
\end{enumerate}

This is in a paragraph:
\begin{inparaenum}
\item item one and
\item item two.
\end{inparaenum}
This is in a paragraph.

\end{document}

Answer 1

I hope I understand the question correctly: enumitem package allows you to define inline lists very conveniently. The (now-)commented settings can be also defined at the preamble globally.

\documentclass[11pt]{amsart}
\usepackage[inline]{enumitem}
\setlist[enumerate,1]{label=\textit{\alph*)}}

\begin{document}

This is a list:
\begin{enumerate}%[label=\textit{\alph*)}]
\item item one
\item item two
\end{enumerate}

This is in a paragraph:
\begin{enumerate*}%[label=\textit{\alph*)}]
\item item one and
\item item two.
\end{enumerate*}
This is in a paragraph.

\end{document}