123ssss

import sys

from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *

from PyQt5 import *


class Window(QMainWindow):
    def __init__(self):
        super().__init__()

        self.init_ui()

    def init_ui(self):
        font = "Verdana"
        self.setWindowTitle('Licznik blokow')
        self.setGeometry(100, 100, 800, 600)

        self.label = QLabel(self)
        self.canvas = QPixmap(600, 600)
        self.canvas.fill(QColor(Qt.lightGray))
        self.label.setPixmap(self.canvas)
        self.setCentralWidget(self.label)

        self.btn1 = QPushButton("GORA", self)
        self.btn1.setGeometry(620, 40, 150, 50)
        self.btn1.clicked.connect(self.gora)

        self.btn2 = QPushButton("DOL", self)
        self.btn2.setGeometry(620, 510, 150, 50)
        self.btn2.clicked.connect(self.dol)


        self.show()

    def gora(self):
        print("gora")
        painter = QPainter(self.label.pixmap())
        painter.setPen(QPen(Qt.black), 3, Qt.SolidLine)
        painter.fillRect(0,0,600,600, QColor(Qt.lightGray))

        painter.drawLine(100, 100, 150, 200)
        painter.end()
        self.update()

    def dol(self):
        print("dol")

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