code: def testPriority(self):
      feed4 = RealtimeFeed([], None)
      feed3 = RealtimeFeed([], None)
      feed2 = RealtimeFeed([], 3)
      feed1 = RealtimeFeed([], 0)
  
      disp = dispatcher.Dispatcher()
      disp.addSubject(feed3)
      disp.addSubject(feed2)
      disp.addSubject(feed1)
      self.assertEqual(disp.getSubjects(), [feed1, feed2, feed3])
  
      disp = dispatcher.Dispatcher()
      disp.addSubject(feed1)
      disp.addSubject(feed2)
      disp.addSubject(feed3)
      self.assertEqual(disp.getSubjects(), [feed1, feed2, feed3])
  
      disp = dispatcher.Dispatcher()
      disp.addSubject(feed3)
      disp.addSubject(feed4)
      disp.addSubject(feed2)
      disp.addSubject(feed1)
      self.assertEqual(disp.getSubjects(), [feed1, feed2, feed3, feed4])
  
imports: import datetime
  import copy
  from six.moves import xrange
  from .None import common
  from pyalgotrade import observer
  from pyalgotrade import dispatcher
label_desc: Use image node_id 6 for calling the DispatcherTestCase obj's underlying member method code with example usage: obj.testPriority() without return types