from PyQt5 import QtCore, QtGui, QtWidgets, QtWebKit, QtWebKitWidgets

class Window(QtWidgets.QWidget):
    def __init__(self):
        QtWidgets.QWidget.__init__(self)
        self.view = QtWebKitWidgets.QWebView(self)
        self.view.settings().setAttribute(
            QtWebKit.QWebSettings.DeveloperExtrasEnabled, True)
        self.inspector = QtWebKitWidgets.QWebInspector(self)
        self.inspector.setPage(self.view.page())
        self.inspector.hide()
        self.splitter = QtWidgets.QSplitter(self)
        self.splitter.setOrientation(QtCore.Qt.Vertical)
        self.splitter.addWidget(self.view)
        self.splitter.addWidget(self.inspector)
        layout = QtWidgets.QVBoxLayout(self)
        layout.setContentsMargins(0, 0, 0, 0)
        layout.addWidget(self.splitter)
        QtWidgets.QShortcut(QtGui.QKeySequence('F11'), self,
            self.handleShowInspector)

    def handleShowInspector(self):
        self.inspector.setVisible(self.inspector.isHidden())

if __name__ == '__main__':

    import sys
    app = QtWidgets.QApplication(sys.argv)
    window = Window()
    window.view.load(QtCore.QUrl('http://www.google.com'))
    window.show()
    app.exec_()