code: def setUp(self):
      super().setUp()
      self.current_backend = Store.current_backend
      self.pprinter = PrettyPrinter(show_options=True)
      self.register_custom(
          ExampleElement,
          "backend_1",
          ["plot_custom1"],
          ["style_custom1"],
      )
      self.register_custom(Overlay, "backend_1", ["plot_custom1"])
      self.register_custom(Layout, "backend_1", ["plot_custom1"])
      self.register_custom(
          ExampleElement, "backend_2", ["plot_custom2"]
      )
      Store.current_backend = "backend_1"
  
file_path: holoviews/holoviews/tests/core/test_prettyprint.py
imports: from holoviews import Curve, Element, Layout, Overlay, Store
  from holoviews.core.pprint import PrettyPrinter
  from holoviews.element.comparison import ComparisonTestCase
  from .test_dimensioned import CustomBackendTestCase, ExampleElement
label_desc: Use image node_id 1 for calling the PrettyPrintOptionsTest obj's underlying member method code with example usage: obj.setUp() without return types