def mk_tweet(self, prefix, twitter_ids, video_name, authors, video_url):
		"""
		Generates tweet, conditionally reducing text if too long.

		Should return (examples):
		#lca2017 My Talk Title - @CarlFK http://youtu.be/123456
		#lca2017 My Talk Title - Carl Karsten http://youtu.be/123456
		#lca2017 My Really Long Talk Title That Got Shortened Because It Is Lon... - Carl Karsten http://youtu.be/123456
		"""

		TWITTER_LENGTH_MAX = 140

		# always shorten video_url's (if not already shortened i.e. youtu.be links)
		if len(video_url) > 25:
			video_url = self.shorten(video_url)

		# We have to display certain characters always (i.e. #lca2017, video URL, spaces/dashes between data)
		AVAILABLE_CHARS = TWITTER_LENGTH_MAX - len(prefix) - len(video_url) - 5

		message = '#{prefix} {{video_name}} - {{authors}} {video_url}'.format(
			prefix=prefix,
			video_url=video_url
		)

		# If user has a twitter handle, tweet this, not their name
		if twitter_ids:
			authors = twitter_ids

		# If everything fits, tweet all fields (unshortened)
		if AVAILABLE_CHARS - len(video_name) - len(authors) >= 0:
			return message.format(video_name=video_name, authors=authors)

		# If not, shorten the title
		else:
			MAX_AVAILABLE_TITLE_CHARS = AVAILABLE_CHARS - len(authors)
			shortened_video_name = video_name[:AVAILABLE_CHARS]
			return message.format(video_name=shortened_video_name, authors=authors)