How to solve a webapp2 import error after upgrading Google App Engine launcher?
<p>We just upgraded Google App Engine Launcher on a Mac and a script that was working fine now is throwing a "ImportError: No module named webapp2" error when launching it via PyCharm. </p>

<p>Here is the trace:</p>

<blockquote>
  <p>Traceback (most recent call last):   File
  "/usr/local/google_appengine/google/appengine/runtime/wsgi.py", line
  240, in Handle
      handler = _config_handle.add_wsgi_middleware(self._LoadHandler())   File "/usr/local/google_appengine/google/appengine/runtime/wsgi.py",
  line 299, in _LoadHandler
      handler, path, err = LoadObject(self._handler)   File "/usr/local/google_appengine/google/appengine/runtime/wsgi.py", line
  85, in LoadObject
      obj = <strong>import</strong>(path[0])   File "/Users/Michael/Documents/GitHub/velocitybyathla/main.py", line 17, in
  
      import webapp2 ImportError: No module named webapp2 INFO     2016-06-02 05:39:58,835 module.py:788] default: "GET / HTTP/1.1" 500 -</p>
</blockquote>

<p>We tried adding the path to Python in Google App Engine Launcher as suggested <a href="https://stackoverflow.com/questions/15998801/python-error-importerror-no-module-named-webapp2">here</a> - but the error remains. </p>

<p>webapp2 is clearly installed. It worked before the upgrade and if we do "pip install webapp2" it says it is present. </p>

<p>We also tried "Make Symlinks" without success. </p>

<p>How has Google App Engine Launcher lost its path to the module? How do we fix it?</p>