title: Effect of using sys.path.insert(0, path) and sys.path(append) when loading modules
body: <p>I was recently having a problem with a python ImportError, where the module was found when running on my local computer but not found on the CI server. I solved this problem by swapping <code>sys.path.append(path)</code> in my script with <code>sys.path.insert(0, path)</code> where <code>path</code> is the string module location.</p>
  
  <p>Since this is my module and not an installed package (<a href="https://stackoverflow.com/questions/10095037/why-use-sys-path-appendpath-instead-of-sys-path-insert1-path">related question</a>), why does the order of paths fix this problem?</p>