Python best practices to impletent QThread, progressbar (pyqt5) and sniffer (scapy)

I'm new in python and I want to know the way to improve this code with best practices.

I'm using PyQT5 to create new thread In that thread I'm using scapy to sniff traffic and filter ARP traffic to find devices which are broadcasting the network.

In the complete code I'm filtering IP traffic too, but now I'm working on threads in order that GUI doesn't get freeze.

Here the code:

from PyQt5 import QtGui
from PyQt5.QtWidgets import * # QApplication, QDialog, QProgressBar, QPushButton, QVBoxLayout
import sys
from PyQt5.QtCore import Qt, QThread, pyqtSignal, QRect
from scapy.all import sniff, getmacbyip, ARP, get_if_addr, sr
from time import time, sleep

def scan_network(ProgressBar, sec):

  dict_scan = {}
  start_time = time()
  print (dict_scan)
 
def packet_deploy(change_value: pyqtSignal, start_time: float, dict_scan: dict, sec: int):
  def upload_packet(packet):
    if packet.haslayer("ARP"):
    # upload packet, using passed arguments
      dict_scan[(packet[ARP].hwsrc).replace(":", "").upper()] = packet[ARP].psrc
      LoadingBar(change_value, start_time, sec)
  return upload_packet
  
def LoadingBar(change_value, start_time, sec):
  ellapsed =  int(((time() - start_time)*100) / sec)
  change_value.emit(ellapsed)
  
class MyThread(QThread):
    def __init__(self, myvar, parent = None):
        super(MyThread,self).__init__(parent)
        self.myvar = myvar[0]
        
    change_value = pyqtSignal(int)
    def run(self):
        seconds = self.myvar.txt_From.toPlainText()
        print (seconds)
        sec = 10
        dict_scan = {}
        start_time = time()
        sniff(prn=packet_deploy(self.change_value, start_time, dict_scan, sec), timeout = (sec), store=0)
        print (dict_scan)
        
class Window(QDialog):
    def __init__(self):
        super().__init__()
        self.title = "PyQt5 ProgressBar"
        self.top = 200
        self.left = 500
        self.width = 300
        self.height = 200
        self.setWindowIcon(QtGui.QIcon("icon.png"))
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)
        vbox = QVBoxLayout()
        self.progressbar = QProgressBar()
        self.progressbar.setMaximum(100)
        self.progressbar.setStyleSheet("QProgressBar {border: 2px solid grey;border-radius:8px;padding:1px}"
                                       "QProgressBar::chunk {background:yellow}")
        
        vbox.addWidget(self.progressbar)
        self.button = QPushButton("Start Progressbar")
        self.button.clicked.connect(self.startProgressBar)
        self.button.setStyleSheet('background-color:yellow')
        
        
        self.txt_From = QTextEdit()
        self.txt_From.setObjectName(u"txt_From")
        self.txt_From.setGeometry(QRect(0, 0, 151, 21))
        vbox.addWidget(self.txt_From)
        
        vbox.addWidget(self.button)
        self.setLayout(vbox)
        self.show()
 
    def startProgressBar(self):
        self.thread = MyThread(myvar=[self])
        self.thread.change_value.connect(self.setProgressVal)
        self.thread.start()
 
    def setProgressVal(self, val):
         self.progressbar.setValue(val)
 
 
App = QApplication(sys.argv)
window = Window()
sys.exit(App.exec())