# ParallelTaskGroup

> **Class** in `langchain_parallel`

📖 [View in docs](https://reference.langchain.com/python/langchain-parallel/tasks/ParallelTaskGroup)

Batch task runner backed by the Task Group API.

Use when you have a list of inputs and want them all processed in
parallel. Returns a list of result dicts in the same order as the
input list.

## Signature

```python
ParallelTaskGroup()
```

## Description

**Example:**

```python
group = ParallelTaskGroup()  # processor="lite-fast"
results = group.run(
    inputs=[
        "Founder of Anthropic?",
        "Founder of OpenAI?",
        "Founder of Google DeepMind?",
    ]
)
for inp, out in zip(inputs, results):
    print(inp, "->", out["output"])
```

## Extends

- `_TaskClientMixin`

## Properties

- `processor`
- `task_spec`
- `metadata`

## Methods

- [`run()`](https://reference.langchain.com/python/langchain-parallel/tasks/ParallelTaskGroup/run)
- [`arun()`](https://reference.langchain.com/python/langchain-parallel/tasks/ParallelTaskGroup/arun)

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[View source on GitHub](https://github.com/parallel-web/langchain-parallel/blob/c1f8c1d657b86eaf948c363f84fed6ea6bd65754/langchain_parallel/tasks.py#L722)