PyQt5 实现给无边框widget窗口添加背景图片

#! /usr/bin/env python
# -*- coding:utf-8 -*-
import sys
from PyQt5.QtWidgets import QApplication, QWidget
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QPalette, QBrush, QPixmap 
class NoBorderWindow(QWidget):
  def __init__(self):
    super().__init__()
    self.window_UI()
    self.drawn()  
  
  def window_UI(self):
    self.resize(950, 200) 
    self.setWindowFlags(Qt.FramelessWindowHint)
 
  def drawn(self):
    self.palette = QPalette()
    self.palette.setBrush(QPalette.Background, QBrush(QPixmap("./images/bg.gif")))
    self.setPalette(self.palette)
 
if __name__ == "__main__":
  app = QApplication(sys.argv)
  win = NoBorderWindow()  
  win.show()
  sys.exit(app.exec_())

    palette = QPalette()
    palette.setBrush(QPalette.Background, QBrush(QPixmap(":/pic/images/sysBackground.jpg"))) 
    self.setPalette(palette)