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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 cancel_broadcast(self, broadcast_guid):
        '''
        Cancel a broadcast specified by guid
        '''
        subpath = 'broadcasts/%s/update' % broadcast_guid
        broadcast = {'status': 'CANCELED'}
        bcast_dict = self._call(subpath, method='POST', data=broadcast,
            content_type='application/json')
        return bcast_dict