from qgis.core import QgsProject

from PyQt5.QtWidgets import QAction, QFileDialog

def Upload_Point_Layer(self):
  filename, _filter = QFileDialog.getSaveFileName(
  self.dlg, "Select   output file ","", '*.shp')
  self.dlg.lineEdit.setText(filename)

self.dlg.pushButton.clicked.connect(self.Upload_Point_Layer)

Couldn't load plugin 'Nearest_Neighbour' due to an error when calling its classFactory() method

AttributeError: 'NearestNeighbour' object has no attribute 'dlg'
Traceback (most recent call last):
File "C:/OSGeo4W/apps/qgis/./pythonqgisutils.py", line 335, in startPlugin
plugins[packageName] = package.classFactory(iface)
File "C:/Users/Prachi/AppData/Roaming/QGIS/QGIS3profilesdefault/python/pluginsNearest_Neighbour__init__.py", line 36, in classFactory
return NearestNeighbour(iface)
File "C:/Users/Prachi/AppData/Roaming/QGIS/QGIS3profilesdefault/python/pluginsNearest_NeighbourNearest_Neighbour.py", line 73, in __init__
self.dlg.lineEdit.clear()
AttributeError: 'NearestNeighbour' object has no attribute 'dlg'

if self.first_start == True:
   self.first_start == False
   self.dlg = SaveAttributeDialog()