How to use the icalendar.vText function in icalendar

now = tz.localize(_now)
        if term_id in self.courses:
            for i in self.courses[term_id]:
                for t in i.time:
                    for n, w in enumerate(t['week'][1:]):
                        if int(w):
                            targetTime = datetime.timedelta(days=7 * n + t['weekday']) + the_first_day + CLASS[
                                min(t['time'])]
                            targetEndTime = datetime.timedelta(days=7 * n + t['weekday'], minutes=45) + the_first_day + \
                                            CLASS[max(t['time'])]
                            e = icalendar.Event()
                            e.add('dtstart', tz.localize(targetTime))
                            e.add('dtend', tz.localize(targetEndTime))
                            e['summary'] = "{} {} {}".format(i.name.split('(')[0],
                                                             i.teacher + "老师" if i.teacher else "", t['location'])
                            e['location'] = icalendar.vText(t['location'])
                            # e['SEQUENCE'] = 1
                            e['TRANSP'] = icalendar.vText('OPAQUE')
                            e['status'] = 'confirmed'
                            e.add('created', now)
                            e.add('DTSTAMP', _now)
                            e["UID"] = '{}@sync.pandada8.me'.format(md5(str(targetTime) + i.name))
                            e.add('LAST-MODIFIED', _now)

                            table.add_component(e)
        return table

attendee.params['cn'] = vText('Argo Roots')
        attendee.params['ROLE'] = vText('CHAIR')
        event.add('attendee', attendee, encode=0)

        attendee = vCalAddress('MAILTO:mihkel.putrinsh@artun.ee')
        attendee.params['cn'] = vText('Mihkel Putrinsh')
        attendee.params['ROLE'] = vText('REQ-PARTICIPANT')
        event.add('attendee', attendee, encode=0)

        attendee = vCalAddress('MAILTO:maxm3@example.com')
        attendee.params['cn'] = vText('Max Rasmussen 3')
        attendee.params['ROLE'] = vText('OPT-PARTICIPANT')
        #event.add('attendee', attendee, encode=0)

        attendee = vCalAddress('MAILTO:maxm4@example.com')
        attendee.params['cn'] = vText('Non')
        attendee.params['ROLE'] = vText('NON-PARTICIPANT')
        #event.add('attendee', attendee, encode=0)

        cal.add_component(event)

        event = Event()
        event.add('summary', 'Python meeting about calendaring 2')
        event.add('dtstart', date(2011,4,6))
        event.add('dtend', date(2011,4,6))
        event.add('dtstamp', datetime(2011,4,4,0,10,0,tzinfo=UTC))
        event['uid'] = '20110115T101010/27346262376@mxm.dk'
        event.add('priority', 5)

        attendee = vCalAddress('MAILTO:mihkel.putrinsh@artun.ee')
        attendee.params['cn'] = vText('Mihkel Putrinsh')
        attendee.params['ROLE'] = vText('REQ-PARTICIPANT')

def add_attendee(self, email, cn=None, rsvp=True):
		"""
		Add an attendee to the event. If the event is being sent via an email,
		the recipient should be added as an attendee.

		:param str email: The attendee's email address.
		:param str cn: The attendee's common name.
		:param bool rsvp: Whether or not to request an RSVP response from the
			attendee.
		"""
		attendee = icalendar.vCalAddress('MAILTO:' + email)
		attendee.params['ROLE'] = icalendar.vText('REQ-PARTICIPANT')
		attendee.params['PARTSTAT'] = icalendar.vText('NEEDS-ACTION')
		attendee.params['RSVP'] = icalendar.vText(str(bool(rsvp)).upper())
		attendee.params['CN'] = icalendar.vText(cn or email)
		self._event.add('attendee', attendee)

event_component.add('summary', session.title)
                event_component.add('uid', str(session.id) + "-" + event.identifier)
                event_component.add('geo', (event.latitude, event.longitude))
                event_component.add('location', session.microlocation.name or '' + " " + event.location_name)
                event_component.add('dtstart', tz.localize(session.starts_at))
                event_component.add('dtend', tz.localize(session.ends_at))
                event_component.add('email', event.email)
                event_component.add('description', session.short_abstract)
                event_component.add('url', url_for('event_detail.display_event_detail_home',
                                                   identifier=event.identifier, _external=True))

                for speaker in session.speakers:
                    # Ref: http://icalendar.readthedocs.io/en/latest/usage.html#file-structure
                    # can use speaker.email below but privacy reasons
                    attendee = vCalAddress('MAILTO:' + event.email if event.email else 'undefined@email.com')
                    attendee.params['cn'] = vText(speaker.name)
                    event_component.add('attendee', attendee)

                cal.add_component(event_component)

        return cal.to_ical()

def add_attendee(self, email, cn=None, rsvp=True):
		"""
		Add an attendee to the event. If the event is being sent via an email,
		the recipient should be added as an attendee.

		:param str email: The attendee's email address.
		:param str cn: The attendee's common name.
		:param bool rsvp: Whether or not to request an RSVP response from the
			attendee.
		"""
		attendee = icalendar.vCalAddress('MAILTO:' + email)
		attendee.params['ROLE'] = icalendar.vText('REQ-PARTICIPANT')
		attendee.params['PARTSTAT'] = icalendar.vText('NEEDS-ACTION')
		attendee.params['RSVP'] = icalendar.vText(str(bool(rsvp)).upper())
		attendee.params['CN'] = icalendar.vText(cn or email)
		self._event.add('attendee', attendee)

attendee.params['cn'] = vText('Non')
        attendee.params['ROLE'] = vText('NON-PARTICIPANT')
        #event.add('attendee', attendee, encode=0)

        cal.add_component(event)

        event = Event()
        event.add('summary', 'Python meeting about calendaring 2')
        event.add('dtstart', date(2011,4,6))
        event.add('dtend', date(2011,4,6))
        event.add('dtstamp', datetime(2011,4,4,0,10,0,tzinfo=UTC))
        event['uid'] = '20110115T101010/27346262376@mxm.dk'
        event.add('priority', 5)

        attendee = vCalAddress('MAILTO:mihkel.putrinsh@artun.ee')
        attendee.params['cn'] = vText('Mihkel Putrinsh')
        attendee.params['ROLE'] = vText('REQ-PARTICIPANT')
        event.add('attendee', attendee, encode=0)

        cal.add_component(event)

        self.echo(str(cal), False)

if not end:
                end = obj['when'] + datetime.timedelta(hours=1)
            event.add('dtend', end)

            event.add('location', obj.get('location', 'Unknown'))
            event['uid'] = obj['_id']

            for participant in obj['participants']:
                addr = icalendar.vCalAddress('MAILTO:noone@example.com')

                cn = participant['participant']

                if participant['type'] == 'committee':
                    cn += ' Committee'

                addr.params['cn'] = icalendar.vText(cn)
                #addr.params['ROLE'] = icalendar.vText('COMMITTEE')
                event.add('attendee', addr, encode=0)
                event['organizer'] = addr

            cal.add_component(event)

        return cal.as_string()

for participant in obj['participants']:
                addr = icalendar.vCalAddress('MAILTO:noone@example.com')

                chamber = participant.get('chamber')
                if chamber:
                    cn = chamber_name(obj[obj['level']], chamber) + " "
                else:
                    cn = ""

                cn += participant['participant']

                if participant['type'] == 'committee':
                    cn += ' Committee'

                addr.params['cn'] = icalendar.vText(cn)
                #addr.params['ROLE'] = icalendar.vText('COMMITTEE')
                event.add('attendee', addr, encode=0)
                event['organizer'] = addr

            cal.add_component(event)

        return cal.as_string()

event.add("dtstart", post_election.election.start_time)
            event.add("dtend", post_election.election.end_time)
            event.add(
                "DESCRIPTION",
                "Find out more at {}/elections/{}/".format(
                    settings.CANONICAL_URL, postcode.replace(" ", "")
                ),
            )
            if polling_station.get("polling_station_known"):
                geometry = polling_station["polling_station"]["geometry"]
                if geometry:
                    event["geo"] = "{};{}".format(
                        geometry["coordinates"][0], geometry["coordinates"][1]
                    )
                properties = polling_station["polling_station"]["properties"]
                event["location"] = vText(
                    "{}, {}".format(
                        properties["address"].replace("\n", ", "),
                        properties["postcode"],
                    )
                )

            cal.add_component(event)

        return HttpResponse(cal.to_ical(), content_type="text/calendar")

def duplicate(self):
        """duplicate this event's PROTO event

        :rtype: Event
        """
        new_uid = generate_random_uid()
        vevent = self._vevents['PROTO'].copy()
        vevent['SEQUENCE'] = 0
        vevent['UID'] = icalendar.vText(new_uid)
        vevent['SUMMARY'] = icalendar.vText(vevent['SUMMARY'] + ' Copy')
        event = self.fromVEvents([vevent])
        event.calendar = self.calendar
        event._locale = self._locale
        return event