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<@ULVA73B9P> is there any way for a task that is being mapped to access the index of the item in the mapped list its processing (without having to map of a list of `(index, data)` tuples?)

:white_check_mark: thought for 242.9 seconds

Yes. In Prefect 3.x, a mapped task can read its mapping “index” from the runtime context via the task run’s dynamic key.

- Inside the task, use `get_run_context()` and read `ctx.task_run.dynamic_key`
- It’s a string; for mapped runs it will be "0", "1", "2", … corresponding to the position

Example:
```
from prefect import flow, task
from prefect.context import get_run_context

@task
def process(item):
    ctx = get_run_context()
    idx = int(ctx.task_run.dynamic_key)  # "0", "1", ... -&gt; int
    print(f"Processing index={idx}, item={item}")
    return idx, item

@flow
def main():
    items = ["a", "b", "c"]
    return process.map(items)

if __name__ == "__main__":
    main()
```

Notes:
- `dynamic_key` is not exposed via `prefect.runtime.task_run`; you need `get_run_context()` inside the task.
- For maximum explicitness/portability, passing the index yourself (e.g., `process.map(range(len(items)), items)`) is still the most transparent approach, but the above avoids changing your mapping inputs.