code: def test_buttonclick_event_callbacks() -> None:
      button = Button()
      test_callback = EventCallback()
      button.on_event(events.ButtonClick, test_callback)
      assert test_callback.event_name is None
      button._trigger_event(events.ButtonClick(button))
      assert test_callback.event_name == events.ButtonClick.event_name
  
imports: from __future__ import annotations
  import pytest
  from bokeh.core.serialization import Deserializer
  from bokeh.models import Button, Div, Plot, TextInput
  from bokeh import events
label_desc: Use image node_id 28 for calling a global function with example usage: test_buttonclick_event_callbacks() without return types