'Retrieve the latest data file to a specified local path with a url.'

def fetch_file(self):

    socket.setdefaulttimeout(10)
    try:
        urllib.urlretrieve(self.url, self.tmp_path, self.set_progress)
        self.replace_old()
        self.finish_trigger.emit(1, 0)
    except:
        self.finish_trigger.emit(1, 1)
