code: def test_signal_proxy_no_slot_start(qapp):
      """Test the connect mode of SignalProxy without slot at start`"""
      sender = Sender(parent=qapp)
      receiver = Receiver(parent=qapp)
      proxy = SignalProxy(
          sender.signalSend, delay=0.0, rateLimit=0.6, threadSafe=False
      )
  
      assert proxy.blockSignal is True
      assert proxy is not None
      assert sender is not None
      assert receiver is not None
  
      sender.signalSend.emit()
      proxy.flush()
      qapp.processEvents(
          QtCore.QEventLoop.ProcessEventsFlag.AllEvents, 10
      )
      assert receiver.counter == 0
  
      # Start a connect
      proxy.connectSlot(receiver.slotReceive)
      assert proxy.blockSignal is False
      sender.signalSend.emit()
      proxy.flush()
      qapp.processEvents(
          QtCore.QEventLoop.ProcessEventsFlag.AllEvents, 10
      )
      assert receiver.counter > 0
  
      # An additional connect should raise an AssertionError
      with pytest.raises(AssertionError):
          proxy.connectSlot(receiver.slotReceive)
  
file_path: pyqtgraph/tests/test_signalproxy.py
imports: import pytest
  from pyqtgraph import SignalProxy
  from pyqtgraph.Qt import QtCore, mkQApp
label_desc: Use image node_id 4 for calling a global function with example usage: test_signal_proxy_no_slot_start(qapp) without return types