title: Gevent shows "AttributeError: 'module' object has no attribute 'join'"
body: <p>i am new to gevent. While i am running the following code: </p>
  
  <pre><code>import gevent
  
  def foo():
    print('Running in foo')
    gevent.sleep(0)
    print('Explicit context switch to foo again')
  
  def bar():
    print('Explicit context to bar')
    gevent.sleep(0)
    print('Implicit context switch back to bar')
  
  gevent.joinall([
  gevent.spawn(foo),
  gevent.spawn(bar),
  ])
  </code></pre>
  
  <p>I am getting this error:</p>
  
  <pre><code>Traceback (most recent call last):
  File "ex.py", line 13, in &lt;module&gt;
  gevent.join([
  AttributeError: 'module' object has no attribute 'join'
  </code></pre>