what is wrong with my code?

[53535]

from PyQt5 import QtCore, QtGui, QtWidgets
import sqlite3
from PyQt5.QtWidgets import QMainWindow, QApplication,QFileDialog,QLabel
import os

def get_file_name(self):

        file_filter= "data file (*.SQLite3)"
        fname = QFileDialog.getOpenFileName(
            parent=self,
            caption="select a file",
            directory=os.getcwd(),
            filter=file_filter
        )

        print(fname)
get_file_name()

Error:
TypeError: get_file_name() missing 1 required positional argument: 'self'