1. getOpenFileName
newFileName, newFileType = QFileDialog.getOpenFileName(self, "Choose File", self.filePath, "Excel (*.xlsx);;Excel (*.xls);;All Files (*)")
2. getExistingDirectory
newFilePath = QFileDialog.getExistingDirectory(self, 'Explorer Folder', self.filePath)
if newFilePath == "":
newFilePath = self.filePath
else:
self.filePath = newFilePath
