class ConferenceSpeaker(SpeakerBase):

    def clean_twitter_username(self):

        value = self.twitter_username

        if value.startswith("@"):

            value = value[1:]

        return value

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

        self.experience_html = parse(self.experience)

        self.twitter_username = self.clean_twitter_username()

        return super(ConferenceSpeaker, self).save(*args, **kwargs)

    twitter_username = models.CharField(

        max_length=15,

        blank=True,

        help_text=_(u"Your Twitter account")

    )

    first_time = models.BooleanField(

        blank=True,

        default=False,

        verbose_name=_("First-time speaker?"),

        help_text=_("Check this field if this is your first time speaking "

                    "at a technical conference."),

        )

    experience = models.TextField(blank=True, help_text=_

        ("List any past speaking experience you have. This can include "

         "user groups, meetups, or presentations at work or school.  Edit "

         "using <a href='http://warpedvisions.org/projects/"

         "Markdown</a>."),

         verbose_name=_("Past speaking experience"),

    )

    experience_html = models.TextField(blank=True)

    travel_assistance = models.BooleanField(

        blank=True,

        default=False,

        verbose_name=_("Travel assistance required?"),

        help_text=_("Check this field if you require travel assistance to get "

                    "to North Bay Python in Petaluma, California."),

    )

    lodging_assistance = models.BooleanField(

        blank=True,

        default=False,

        verbose_name=_("Lodging assistance required?"),

        help_text=_("Check this field if you require lodging assistance in "

                    "Petaluma, California during North Bay Python."),

    )

    home_city = models.CharField(

        blank=True,

        max_length=127,

        help_text=_("Which city (and state, and country) will you be "

                    "traveling from to get to North Bay Python?"),

    )

    minority_group = models.CharField(blank=True, max_length=256,

        verbose_name=_("Diversity statement"),

        help_text=_("If you are a member of one or more groups that are "

                    "under-represented in the tech industry, you may list "