How to create a new environment with mdframed and lstlisting? [duplicate]

Question

I want to create a new environment that wraps mdframed and lstlisting together as shown below, however that does not work for me as it does not compile. Any ideas what the issue is and how to define a new environment similar to the mine below?

\documentclass{llncs}
\pagestyle{plain}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[scaled]{beramono}
\usepackage{xcolor}

\usepackage{mdframed}
\definecolor{light-gray}{gray}{0.95} 

\usepackage{listings}
\lstdefinelanguage{Sage}[]{Python}
{morekeywords={False,sage,True},sensitive=true}
\lstset{
  frame=none,
  showtabs=False,
  showspaces=False,
  showstringspaces=False,
  commentstyle={\ttfamily\color{dgreencolor}},
  keywordstyle={\ttfamily\color{dbluecolor}\bfseries},
  stringstyle={\ttfamily\color{dgraycolor}\bfseries},
  language=Sage,
  basicstyle={\fontsize{10pt}{10pt}\ttfamily},
  aboveskip=0.3em,
  belowskip=0.1em,
  numbers=left,
  numberstyle=\footnotesize
}
\definecolor{dblackcolor}{rgb}{0.0,0.0,0.0}
\definecolor{dbluecolor}{rgb}{0.01,0.02,0.7}
\definecolor{dgreencolor}{rgb}{0.2,0.4,0.0}
\definecolor{dgraycolor}{rgb}{0.30,0.3,0.30}
\newcommand{\dblue}{\color{dbluecolor}\bf}
\newcommand{\dred}{\color{dredcolor}\bf}
\newcommand{\dblack}{\color{dblackcolor}\bf}

\newenvironment{code}
{\begin{mdframed}[
    backgroundcolor=light-gray,
    roundcorner=10pt,
    leftmargin=1,
    rightmargin=1,
    innerleftmargin=10,
    innertopmargin=5,
    innerbottommargin=5,
    outerlinewidth=1,
    linecolor=light-gray
]\begin{lstlisting}[numbers=none]}
{\end{lstlisting}\end{mdframed}}

\begin{document}

\section{Test}

A code example:

\begin{code}
sage: R.<x> = ZZ[]
sage: type(R.an_element())
<type 'sage.rings...Polynomial_integer_dense_flint'>
sage: R.<x,y> = ZZ[]
sage: type(R.an_element())
<type 'sage.rings...MPolynomial_libsingular'>
sage: R = PolynomialRing(ZZ, 'x', implementation='NTL')
sage: type(R.an_element())  # this is a comment
<type 'sage.rings...Polynomial_integer_dense_ntl'>
sage: def abc():
...       """
...       This should be a very long comment.
...       That should span multiple lines.
...       To illustrate what colour Sage comments look like.
...       To get a feel for the color when rendered using LaTeX.
...       """
...       return 2
\end{code}

\end{document}

Answer 1

I suggest to use the tcolorbox package instead of mdframes. Tcolorbox has build-in support for new listings environments:

\documentclass{llncs}
\pagestyle{plain}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[scaled]{beramono}
\usepackage{xcolor}

\usepackage[most]{tcolorbox}
\definecolor{light-gray}{gray}{0.95} 

\usepackage{listings}
\lstdefinelanguage{Sage}[]{Python}
{morekeywords={False,sage,True},sensitive=true}
\lstset{
  frame=none,
  showtabs=False,
  showspaces=False,
  showstringspaces=False,
  commentstyle={\ttfamily\color{dgreencolor}},
  keywordstyle={\ttfamily\color{dbluecolor}\bfseries},
  stringstyle={\ttfamily\color{dgraycolor}\bfseries},
  language=Sage,
  basicstyle={\fontsize{10pt}{10pt}\ttfamily},
  aboveskip=0.3em,
  belowskip=0.1em,
  numbers=left,
  numberstyle=\footnotesize
}
\definecolor{dblackcolor}{rgb}{0.0,0.0,0.0}
\definecolor{dbluecolor}{rgb}{0.01,0.02,0.7}
\definecolor{dgreencolor}{rgb}{0.2,0.4,0.0}
\definecolor{dgraycolor}{rgb}{0.30,0.3,0.30}
\newcommand{\dblue}{\color{dbluecolor}\bf}
\newcommand{\dred}{\color{dredcolor}\bf}
\newcommand{\dblack}{\color{dblackcolor}\bf}

\newtcblisting{code}{
  listing options={numbers=none},
  colback=light-gray,
  enhanced,
  frame hidden,
  sharp corners,
  listing only,
}

\begin{document}

\section{Test}

A code example:

\begin{code}
sage: R.<x> = ZZ[]
%sage: type(R.an_element())
%<type 'sage.rings...Polynomial_integer_dense_flint'>
%sage: R.<x,y> = ZZ[]
%sage: type(R.an_element())
%<type 'sage.rings...MPolynomial_libsingular'>
%sage: R = PolynomialRing(ZZ, 'x', implementation='NTL')
%sage: type(R.an_element())  # this is a comment
%<type 'sage.rings...Polynomial_integer_dense_ntl'>
%sage: def abc():
%...       """
%...       This should be a very long comment.
%...       That should span multiple lines.
%...       To illustrate what colour Sage comments look like.
%...       To get a feel for the color when rendered using LaTeX.
%...       """
%...       return 2
\end{code}

\end{document}