code: def test_defaults(self):
      options = MarkerOptions()
      assert options.hover_text == ""
      assert not options.display_info_box
      assert options.info_box_content == ""
      assert options.label == ""
  
imports: import unittest
  import pytest
  import numpy
  import traitlets
  from ..marker import MarkerOptions, Marker, Markers, Symbol, marker_layer, symbol_layer
label_desc: Use image node_id 1 for calling the MarkerOptionsTests obj's underlying member method code with example usage: obj.test_defaults() without return types