title: File.expand_path("../../Gemfile", __FILE__) How does this work? Where is the file?
body: <p><code>ENV["BUNDLE_GEMFILE"] = File.expand_path("../../Gemfile", __FILE__)</code></p>
  
  <p>I'm just trying to access a .rb file from the some directory and a tutorial is telling me to use this code but I don't see how it is finding the gem file.</p>