new_contents: from PyQt5.QtCore import QObject, pyqtSlot, pyqtSignal
  
  class ContainerProxy(QObject):
      def __init__(self, container, parent = None):
          super().__init__(parent)
  
          self._container = container
  
      @pyqtSlot(str, result = "QVariant")
      def getValue(self, value):
          return self._container.get(value, None)
  
      @pyqtSlot(str, "QVariant")
      def setValue(self, key, value):
          self._container[key] = value
  
      @pyqtSlot(result = int)
      def getCount(self):
          return len(self._container)
  
subject: Add a ContainerProxy class that can be used as a fast accessor for Python containers