def build(self, client, pull=False, usecache=True):
stage = staging.StagedFile(self.sourceimage, self.sourcepath, self.destpath,<EOL>cache_from=self.cache_from)<EOL>stage.stage(self.baseimage, self.buildname)<EOL>
Note:
   `pull` and `usecache` are for compatibility only. They're irrelevant because
   hey were applied when BUILDING self.sourceimage