>>> from prefect.executors import LocalDaskExecutor
>>> import time
>>> @task
... 
  File "<stdin>", line 2
    
    ^
SyntaxError: invalid syntax
>>> def extract_reference_data():
...     time.sleep(10)
...     return 'hej'
... @task
  File "<stdin>", line 4
    @task
    ^
SyntaxError: invalid syntax
>>> 
>>> def extract_live_data(input):
...     time.sleep(10)
...     return f'{input}hejdå'
... @task
  File "<stdin>", line 4
    @task
    ^
SyntaxError: invalid syntax
>>> 
>>> def separate_task():
...     time.sleep(10)
...     return 'hoppsan'
... 
>>> with Flow("Aircraft-ETL",
...           executor=LocalDaskExecutor()) as flow:
...     reference_data = extract_reference_data()
...     live_data = extract_live_data(reference_data)
...     separate_task()
... 
Traceback (most recent call last):
  File "<stdin>", line 3, in <module>
NameError: name 'extract_reference_data' is not defined
>>> flow.run()
[2021-12-07 12:08:44+0100] INFO - prefect.FlowRunner | Beginning Flow run for 'Aircraft-ETL'
[2021-12-07 12:08:44+0100] INFO - prefect.FlowRunner | Flow run SUCCESS: all reference tasks succeeded
<Success: "All reference tasks succeeded.">
>>> # flow.visualize()

separate_task(upstream_tasks=[live_data])