def popitem(self):
        for key in self.iterkeys():
            return (key, self.pop(key))     # This is only run once.
        else:
            raise KeyError('No messages in mailbox')
Verify that the path to the device is a mount point and mounted.  This
dataset/ETHPy150Open babble/babble/include/jython/Lib/mailbox.py/Mailbox.popitem--crossover with--dataset/ETHPy150Open openstack/swift/swift/common/constraints.py/check_mount