def fetch(self, category=CATEGORY_MESSAGE, from_date=DEFAULT_DATETIME):
items = super().fetch(category, from_date)<EOL>return items<EOL>
Fetch the messages from the HyperKitty mailing list archiver.

        The method fetches the mbox files from a remote HyperKitty
        mailing list archiver and retrieves the messages stored on them.

        Take into account that HyperKitty does not provide yet any kind
        of info to know which is the first message on the mailing list.
        For this reason, using a value in `from_date` previous to the
        date where the first message was sent will make to download
        empty mbox files.

        :param category: the category of items to fetch
        :param from_date: obtain messages since this date

        :returns: a generator of messages