class_docstr: Widget that can be inserted into the DOM
code: def _repr_keys(self):
      for key in super(DOMWidget, self)._repr_keys():
          # Exclude layout if it had the default value
          if key == "layout":
              value = getattr(self, key)
              if repr(value) == "%s()" % value.__class__.__name__:
                  continue
          yield key
      # We also need to include _dom_classes in repr for reproducibility
      if self._dom_classes:
          yield "_dom_classes"
  
file_path: catboost/contrib/python/ipywidgets/py2/ipywidgets/widgets/domwidget.py
imports: from traitlets import Unicode
  from .widget import Widget, widget_serialization
  from .trait_types import InstanceDict, TypedTuple
  from .widget_layout import Layout
  from .widget_style import Style
label_desc: Use image node_id 3 for calling the DOMWidget obj's underlying member method code with example usage: obj._repr_keys() without return types