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Hi, I am facing this problem.


Issue: `Scheduled Flow`  fails because task is unable to return value when `Prefect Server` runs the flow with `CloudFlowRunner` . Same Flow runs successfully when I use `flow.run()` . I have attached the code, Prefect UI screenshot, and terminal output of flow.run().

if-else block at lineno 920 in `task_runner.py`  is causing issue. If I return a value from the `function/task` it runs the if-block otherwise else block. line `self.result.write(value, **formatting_kwargs)`  is calling the function with format `self.`  and dictionary `formatting_kwargs` also contains the `self` variable, this self variable contains the object of `Demo`  class.

code
```from prefect import task, Flow
from datetime import timedelta, datetime
from prefect.schedules import IntervalSchedule

class Demo:
    def demo1(self, a: int, b: int) -&gt; int:
        value = a+ b

    def demo2(self, a: int, b: int) -&gt; int:
        return a+b

obj = Demo()
demo1_function = task(Demo.demo1)
demo2_function = task(Demo.demo2)

with Flow("demo-flow") as flow:
    params = {"a": 1, "b": 2}
    demo1_function(obj, **params)
    demo2_function(obj, **params)

start_time = datetime.now() - timedelta(hours=5)
interval_time = timedelta(hours=0, minutes=1, seconds=0)
end_time = datetime.strptime("2022-12-31 23:59:00", "%Y-%m-%d %H:%M:%S")

schedule = IntervalSchedule(
    start_date = start_time,
    interval=interval_time,
    end_date=end_time
    )

flow.run()
flow.schedule = schedule
flow_id = flow.register(project_name="test",
              labels=['Suleman'],
              idempotency_key=flow.serialized_hash())```


this issue resolves when I rename variable `self` .

Hey <@U03HK90HDGQ>, I think making a task out of methods is discouraged in both Prefect 1 and Prefect 2. You can also turn off checkpointing here if it helps. If you get a chance, could you move the code to this thread to keep the main channel cleaner?

Thanks, setting `checkpoint=False` is helpful. I have also removed the code from the main thread.