from metaflow import FlowSpec, step

class BaseFlow(FlowSpec):
    @step
    def start(self):
        print("this is the start")
        self.next(self.step1)

    @step
    def step1(self):
        print("base step 1")
        self.next(self.end)

    @step
    def end(self):
        print("base step end.")


class SubFlow(BaseFlow):
    @step
    def step1(self):
        print("sub step 1")
        self.next(self.step2)

if __name__ == "__main__":
    SubFlow()

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