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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_twitter_id(self, cache=True):
 """Get the twitter id for this artist if it exists Args: Kwargs: Returns: A twitter ID string Example: u'BigBoi' """

        if not (cache and ('twitter' in self.cache)):
            response = self.get_attribute('twitter')
            self.cache['twitter'] = response['artist'].get('twitter')
        return self.cache['twitter']