title: Using tikz to draw graph with multiple edges between each other
body: <p>I am trying to draw a (undirected) graph using the Tikz package, such that there exist multiple edges between some nodes in the graph. Is it possible to do such a thing? I tried the following code to try and get atleast two edges between the nodes, but to no avail:</p>
  
  <pre><code>\begin{tikzpicture}
  [scale=.8,auto=left,every node/.style={circle,fill=blue!20}]
  \node (nA) at (1,10) {A};
  \node (nB) at (9,10) {B};
  \node (nC) at (5,8)  {C};
  \node (nD) at (5,6)  {D};
  
  \foreach \from/\to in {nA/nC,nA/nD,nC/nB,nD/nB,nC/nA,nD/nA,nB/nD,nB/nC}
  \draw (\from)--(\to);
  \end{tikzpicture}
  </code></pre>
  
  <p>Could someone help me out with this? Thanks!</p>