new_contents: 
  import cv_widget
  
  class CameraWidget(cv_widget.CvWidget):
      
      def __init__(self, fixed_size):
          cv_widget.CvWidget.__init__(self, fixed_size)
      
      def set_error(self):
          pass
      
      def set_target_data(self, data):
          img, data = data
          
          self.set_from_np(img)
      
      
subject: Add in camera widget, not complete yet