correct code:

import sys
import socket
import threading
import time

from PySide6.QtWidgets import QApplication, QMainWindow, QWidget, QVBoxLayout, QHBoxLayout, QLabel, QPushButton, \
    QTableWidget, QTableWidgetItem, QCalendarWidget, QAbstractItemView

from PySide6.QtGui import QPixmap
from PySide6.QtCore import Qt


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Client NAME_1")
        self.setGeometry(100, 100, 800, 600)

        # Create a central widget and set a layout for it
        central_widget = QWidget()
        self.setCentralWidget(central_widget)
        layout = QVBoxLayout()
        central_widget.setLayout(layout)

        # Create labels for user and computer
        user_label = QLabel("User:")
        user_name_label = QLabel("")
        computer_label = QLabel("Computer:")
        computer_name_label = QLabel("")
        layout.addWidget(user_label)
        layout.addWidget(user_name_label)
        layout.addWidget(computer_label)
        layout.addWidget(computer_name_label)

        # Create buttons for start and exit
        start_button = QPushButton("Start")
        exit_button = QPushButton("Exit")
        layout.addWidget(start_button)
        layout.addWidget(exit_button)

        # Create a table for work time and birthdays
        table_widget = QTableWidget()
        table_widget.setColumnCount(3)
        table_widget.setHorizontalHeaderLabels(["Work Time / Birthdays", "Scheduler", "My Tasks"])
        table_widget.