title: APScheduler(Advance Python Scheduler) ImportError: No module named scheduler
body: <p>I am having following import error</p>
  
  <p>"ImportError: No module named scheduler" </p>
  
  <p>when I run the following python script:</p>
  
  <pre><code>"""
  Demonstrates how to use the blocking scheduler to schedule a job that execute$
  """
  
  from datetime import datetime
  import os
  
  from apscheduler.scheduler import BlockingScheduler
  
  
  def tick():
   print('Tick! The time is: %s' % datetime.now())
  
  
  if __name__ == '__main__':
   scheduler = BlockingScheduler()
   scheduler.add_job(tick, 'interval', seconds=3)
   print('Press Ctrl+{0} to exit'.format('Break' if os.name == 'nt' else 'C'$
  
  try:
      scheduler.start()
  except (KeyboardInterrupt, SystemExit):
      pass
  </code></pre>
  
  <p>I have installed APS scheduler using: 
  sudo pip install apscheduler</p>
  
  <p>I have also upgraded using:
  sudo pip install apscheduler --upgrade
  Also upgraded my system using "sudo apt-get install update &amp;&amp; sudo apt-get upgrade" </p>