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Hi there! Is it possible to filter while using map and return_state? I want to get all the states returned from a task map, and then pass the states onto another funciton so I may handle failed states. i.e:

`# with each of the files, transform it into the APVM schema`
    `apvms = transform_answer_to_apvm_schema.map(`
        `answers,`
        `unmapped(apvm_template),`
        `unmapped(apvm_template_mappings),`
        `return_state=True,`
    `)`

    `paths = write_apvm_to_storage.map(apvms, answers)`

But in the above example, only the successful results will map to the write to storage function. Am I best off not using map and iterating through all the states using a loop?

hi <@U05HHPHKEA3>

how would you like to handle failed states in terms of writing to storage?

you can filter out whichever states you like thanks to `return_state=True` and handle each as you need to downstream

does that answer your question?

```from prefect import flow, task
from prefect.states import Completed, Failed, State
from prefect.utilities.collections import listrepr

@task
def add_42(v: int) -&gt; int:
    try:
        return v + 42
    except Exception as e:
        return Failed(message=f"eek!: {e!r}")

def handler(state) -&gt; State:
    print(f"Handling state: {state!r}")
    return state
    
@task
def write_to_storage(v):
    print(f"Writing {v!r} to storage")

@flow(log_prints=True)
def foo():
    result_states = add_42.map([1, None, 3], return_state=True)

    completed, failed = (
        filter(lambda s: s.is_completed(), result_states),
        filter(lambda s: s.is_failed(), result_states),
    )
    
    failures = list(map(handler, failed))
    
    write_to_storage.map(completed)
    
    return Completed(message=f"Finished with some failures: {listrepr(failures)}")
    
if __name__ == "__main__":
    foo()```