title: imageio - ValueError: Could not find a format to read the specified file in mode 'i'
body: <p>I have a series of SVG images (generated from <code>matplotlib</code>) and I want to combine them into a GIF image.</p>
  <p>Since I read this <a href="https://stackoverflow.com/a/35943809/10811334">question</a>, I tried <code>imageio</code>, but it raised <code>ValueError: Could not find a format to read the specified file in mode 'i'</code> at <code>imread(str(i)+'.svg')</code> part. How to fix this?</p>