PYQT5 Python.Как сделать неизменяемым панель инструментов, то есть зафиксировать в определённой плоскости?

from PyQt5.QtWidgets import QApplication, QWidget, QPushButton, QHBoxLayout, QVBoxLayout, QLabel, \
QSlider, QStyle, QSizePolicy, QFileDialog, QAction, qApp, QMainWindow
import sys
from PyQt5.QtMultimedia import QMediaPlayer, QMediaContent
from PyQt5.QtMultimediaWidgets import QVideoWidget
from PyQt5.QtGui import QIcon, QPalette
from PyQt5.QtCore import Qt, QUrl
from PyQt5 import Qt


class Example(QMainWindow):

def __init__(self):

    super().__init__()

    self.setWindowTitle("Media Player")
    self.setGeometry(350, 100, 700, 500)
    self.setWindowIcon(QIcon('F:/img_4_python/mediaplayer.png'))

    self.secondWin = None

    self.threeWin = None

    self.initUI()

    self.show()


def initUI(self):

    hbox = QHBoxLayout()

    exitAction = QAction(QIcon('F:/img_4_python/exit.png'), 'Exit', self)
    exitAction.setShortcut('Alt+F4')
    exitAction.triggered.connect(qApp.quit)
    
    self.toolbar = self.addToolBar('Exit')
    self.toolbar.addAction(exitAction)

    videoAction = QAction(QIcon('F:/img_4_python/video.png'), 'Play Video', self)
    videoAction.setShortcut('Ctrl+Q')
    videoAction.triggered.connect(qApp.quit)

    self.toolbar = self.addToolBar('Open Video')
    self.toolbar.addAction(videoAction)

    musicAction = QAction(QIcon('F:/img_4_python/mp3.png'), 'Play Song', self)
    musicAction.setShortcut('Ctrl+E')
    musicAction.triggered.connect(qApp.quit)

    self.toolbar = self.addToolBar('Open Song')
    self.toolbar.addAction(musicAction)



if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())