title: How to set the width and heigth of the ouput image in Pygraphviz
body: <p>I am creating a .png file like this:</p>
  
  <pre><code>import pygraphviz as pgv
  G = pgv.AGraph()
  G.add_nodes("a")
  G.add_edge("b", "c")
  
  G.layout()
  G.draw("output.png")
  </code></pre>
  
  <p>How can I set the size of the output image?</p>