'Returns an iterator of :class:`Message` resources.
:param date after: Only list calls started after this datetime
:param date before: Only list calls started before this datetime'

@normalize_dates
def iter(self, from_=None, to=None, before=None, after=None, date_sent=None, **kwargs):

    kwargs['From'] = from_
    kwargs['To'] = to
    kwargs['DateSent<'] = before
    kwargs['DateSent>'] = after
    kwargs['DateSent'] = parse_date(date_sent)
    return super(Messages, self).iter(**kwargs)
