def _TryTakeControl(self, client, detect_abandonment, callback):
    former_owner_id = self.owner_id
    self._GenerateOwnerId()
    self.expiration = time.time() + Lock.ABANDONMENT_SECS if detect_abandonment else None
    self.Update(client, expected={'owner_id': former_owner_id}, callback=callback)
Return the message's main content type.
dataset/ETHPy150Open viewfinderco/viewfinder/backend/db/lock.py/Lock._TryTakeControl--crossover with--dataset/ETHPy150Open kleientertainment/ds_mod_tools/pkg/win32/Python27/Lib/email/message.py/Message.get_content_maintype