pyqt 不规则形状窗口显示

#coding=utf-8
import sys
from PyQt5.QtCore import Qt
from PyQt5.QtWidgets import QWidget, QApplication
from PyQt5.QtGui import QPixmap, QPainter, QBitmap, QCursor
import PyQt5.QtCore as QtCore
 
class PixWindow(QWidget):  # 不规则窗体
    def __init__(self):
        super().__init__()
        self.pix = QPixmap('0.png')  # 蒙版
        windowWidth = 200
        windowHeight = 200
        self.resize(windowWidth, windowHeight)
        self.pix = self.pix.scaled(int(windowWidth), int(windowHeight))
        self.setMask(self.pix.mask())
        self.setWindowFlags(Qt.FramelessWindowHint | QtCore.Qt.WindowStaysOnTopHint)  # 设置无边框和置顶窗口样式
 
    def paintEvent(self, event):  # 绘制窗口
        paint = QPainter(self)
        paint.drawPixmap(0, 0, self.pix.width(), self.pix.height(), self.pix)
 
 
if __name__ == '__main__':
    app = QApplication(sys.argv)
    win = PixWindow()
    win.show()
    sys.exit(app.exec_())