Как решить ошибку TypeError: expected str, bytes or os.PathLike object, not tuple?

Небольшой код для вывода заголовков из csv в ListWidget, но на стадии загрузки файла выскакивает ошибка: TypeError: expected str, bytes or os.PathLike object, not tuple

Код ui:

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(374, 327)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.centralwidget)
        self.verticalLayout.setObjectName("verticalLayout")
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        self.pushButton.setObjectName("pushButton")
        self.verticalLayout.addWidget(self.pushButton)
        self.listWidget = QtWidgets.QListWidget(self.centralwidget)
        self.listWidget.setObjectName("listWidget")
        self.verticalLayout.addWidget(self.listWidget)
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 374, 22))
        self.menubar.setObjectName("menubar")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.pushButton.setText(_translate("MainWindow", "PushButton"))

Сам скрипт:

class TEST(QtWidgets.QMainWindow, Ui_Window.Ui_MainWindow):
    def __init__(self):
        super(TEST, self).__init__()
        self.setupUi(self)
        assert isinstance(self.pushButton, object)
        self.pushButton.clicked.connect(self.select_file)

    def select_file(self):
        self.f_name = QtWidgets.QFileDialog.getOpenFileName(self, "Choose file")
        with open(self.f_name, newline='') as D:
            reader = csv.reader(D, delimiter=";")
            count = 0
            for row in reader:
                if count == 0:
                    list_m = f'{" ".join(row)}'
                    for item in list_m:
                        self.listWidget.addItem(item)
                else:

                    DEPH = f'{row[0]}'  # - {row[1]}'
                    count += 1
if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    ui = TEST()
    ui.show()
    app.exec_()
    sys.exit(app.exec_())

Подскажите пожалуйста как решить проблему