"""

    the full conference for a specific year, e.g. US PyCon 2012.

    """

    title = models.CharField(_("title"), max_length=100)

    # when the conference runs

    start_date = models.DateField(_("start date"), null=True, blank=True)

    end_date = models.DateField(_("end date"), null=True, blank=True)

    # timezone the conference is in

    timezone = TimeZoneField(_("timezone"), blank=True)

    def __unicode__(self):

        return self.title

    def save(self, *args, **kwargs):

        super(Conference, self).save(*args, **kwargs)

        if self.id in CONFERENCE_CACHE:

            del CONFERENCE_CACHE[self.id]

    def delete(self):

        pk = self.pk

        super(Conference, self).delete()

            del CONFERENCE_CACHE[pk]

        except KeyError:

            pass

    class Meta(object):

        verbose_name = _("conference")

        verbose_name_plural = _("conferences")

    "Talks", "Expo", "Sprints", that may have its own review and

    scheduling process.

    """

    conference = models.ForeignKey(Conference, verbose_name=_("conference"))

    name = models.CharField(_("name"), max_length=100)

    slug = models.SlugField()

    # when the section runs

    start_date = models.DateField(_("start date"), null=True, blank=True)

    end_date = models.DateField(_("end date"), null=True, blank=True)

    def __unicode__(self):

        return "%s %s" % (self.conference, self.name)

    class Meta(object):

        verbose_name = _("section")

        verbose_name_plural = _("sections")