def write_append(self, path, content):
        if self.files not in path:
            self.files[path] = {
                "isdir": False,
                "content": "Hello World",
                "gid": 100,
                "uid": 100,
                "mode": 0o700
                }

        self.files[path]["content"] = self.files[path]["content"] + content
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/tests/unit/virt/disk/vfs/fakeguestfs.py/GuestFS.write_append/swapped operands of `not in`