title: Does the `shell` in `shell=True` in subprocess means `bash`?
body: <p>I was wondering whether <code>subprocess.call("if [ ! -d '{output}' ]; then mkdir -p {output}; fi",shell=True)</code> will be interpreted by <code>sh</code> or<code>zsh</code> instead of <code>bash</code> in different server? </p>
  
  <p>Anyone has ideas about this?  </p>
  
  <p>What should I do to make sure that it's interpreted by <code>bash</code>?</p>