title: Pip install package from private github repo in google cloud appengine
body: <p>I am using google cloud appengine and deploying with <code>gcloud app deploy</code> and a standard <code>app.yaml</code> file. My requirements.txt file has one private package that is fetched from github (<code>git+ssh://git@github.com/...git</code>). This install works locally, but when I run the deploy I get </p>
  
  <pre><code>Host key verification failed.
  fatal: Could not read from remote repository.
  </code></pre>
  
  <p>This suggests there is no ssh key when installing. Reading docs (<a href="https://cloud.google.com/appengine/docs/standard/python3/specifying-dependencies" rel="nofollow noreferrer">https://cloud.google.com/appengine/docs/standard/python3/specifying-dependencies</a>) it appears that this just isn't an option??? </p>
  
  <pre><code>Dependencies are installed in a Cloud Build environment that does not provide access to SSH keys. Packages hosted on repositories that require SSH-based authentication must be copied into your project directory and uploaded alongside your project's code using the pip package manager.
  </code></pre>
  
  <p>To me this seems severely not-optimal - the whole point of factoring out code into a package was to be able to avoid duplication in repos. Now, if I want to use appengine, you're telling me this not possible?</p>
  
  <p>Is there really no workaround?</p>