code: def __init__(self, param, depth):
      # Bind emitter to self to avoid garbage collection
      self.emitter = Emitter()
      self.sigChanging = self.emitter.sigChanging
      self._suffix = None
      super().__init__(param, depth)
  
file_path: pyqtgraph/pyqtgraph/parametertree/parameterTypes/slider.py
imports: import numpy
  from ...Qt import QtCore, QtWidgets
  from ..Parameter import Parameter
  from .basetypes import Emitter, WidgetParameterItem
label_desc: Use image node_id 1 to create a new SliderParameterItem object from inherited base classes: WidgetParameterItem with example: obj = SliderParameterItem(param, depth)