code: def make_context(self, docker_file=None):
          
          kwargs = {"silent_build": self.harpoon.silent_build, "extra_context": self.commands.extra_context}
          if docker_file is None:
              docker_file = self.docker_file
          with ContextBuilder().make_context(self.context, **kwargs) as ctxt:
              self.add_docker_file_to_tarfile(docker_file, ctxt.t)
              yield ctxt
docs: Determine the docker lines for this image