code: def test_group_connect(self):
      grp = EmitterGroup(source=self, em1=Event)
      grp.connect(self.record_event)
      self.result = None
      ev = grp.em1(test_key=1)
      self.assert_result(
          event=ev, source=self, sources=[self, self], test_key=1
      )
  
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 8 for calling the TestGroups obj's underlying member method code with example usage: obj.test_group_connect() without return types