docstr: The EmitterGroup auto-connect
docstr_tok: ["The","EmitterGroup","auto-connect"]
code: def test_group_autoconnect(self):
      """The EmitterGroup auto-connect"""
  
      class Source:
          def on_em1(self, ev):
              self.result = 1
  
          def em2_event(self, ev):
              self.result = 2
  
          def em3_event(self, ev):
              self.result = 3
  
      src = Source()
      grp = EmitterGroup(source=src, em1=Event, auto_connect=False)
      src.result = None
      grp.em1()
      assert src.result is None
  
      grp = EmitterGroup(source=src, em1=Event, auto_connect=True)
      src.result = None
      grp.em1()
      assert src.result == 1
  
      grp.auto_connect_format = "%s_event"
      grp.add(em2=Event)
      src.result = None
      grp.em2()
      assert src.result == 2
  
      grp.add(em3=Event, auto_connect=False)
      src.result = None
      grp.em3()
      assert src.result is None
  
imports: import unittest
  import copy
  from vispy.util.event import Event, EventEmitter, EmitterGroup
  from vispy.util import use_log_level
  from vispy.testing import run_tests_if_main, assert_true, assert_raises
label_desc: Use image node_id 6 for calling the TestGroups obj's underlying member method code with example usage: obj.test_group_autoconnect() without return types