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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_event_loop():
 """Return a EventLoop instance. A new instance is created for each new HTTP request. We determine that we're in a new request by inspecting os.environ, which is reset at the start of each request. Also, each thread gets its own loop. """

  ev = _state.event_loop
  if not os.getenv(_EVENT_LOOP_KEY) and ev is not None:
    ev.clear()
    _state.event_loop = None
    ev = None
  if ev is None:
    ev = EventLoop()
    _state.event_loop = ev
    os.environ[_EVENT_LOOP_KEY] = '1'
  return ev