pyqt repaint

In PyQt, you can use the `repaint()` method to update the appearance of a widget or the entire application.

The `repaint()` method schedules a paint event for the widget, which will cause the widget to be repainted at the next available opportunity.

Here's an example of how to use `repaint()` to update the appearance of a widget:

import sys
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton

class MyWidget(QWidget):
    def __init__(self):
        super().__init__()
        self.button = QPushButton('Click me', self)
        self.button.clicked.connect(self.on_button_clicked)

    def on_button_clicked(self):
        self.button.setText('Clicked!')
        self.repaint()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    widget = MyWidget()
    widget.show()
    sys.exit(app.exec_())

In this example, we create a `QPushButton` and connect its `clicked` signal to a method that changes the text of the button and calls `repaint()` to update its appearance.

When the button is clicked, its text changes to "Clicked!" and the widget is repainted to reflect the change.