def METHOD_NAME(self, data=None):
    html = data or self.retrieve_data()
    m = re.search(self.KEY_PATTERN, html)
    if m is not None:
        self.key = m.group(1).strip()
        self.log_debug(f"Key: {self.key}")
        return self.key
    else:
        self.log_warning(self._("Key pattern not found"))
        return None