@abc.abstractmethod
    def remove_file(self, host, dst_path, on_execute, on_completion):
Objects are updated by first filtering the candidates into a queryset
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/virt/libvirt/volume/remotefs.py/RemoteFilesystemDriver.remove_file--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/tests/modeltests/update/tests.py/AdvancedTests.test_update