<reasoning_content>
*   Goal: Implement a basic `JobQueue` class in Python.
    *   Required methods:
        *   `add_job(job_id: str, data: dict) -> str`: Add a job, return `job_id`.
        *   `get_result(job_id: str) -> dict | None`: Get the result of a completed job.
    *    Requirements:
        *   FIFO order (First-In-First-Out).
        *   Internal storage for jobs until processed.
        *   Unique `job_id`.
    *    Output constraints: Python code only, no explanations.

    *   A list or a `collections.deque` can handle the FIFO queue of jobs.
    *   A dictionary can store the results of completed jobs for easy lookup by `job_id`.
    *   Since the prompt asks for a "Job Queue", I should consider how "processing" happens. The prompt doesn't explicitly say I need to write a worker thread, but it asks for a `JobQueue` class structure.
    *   Actually, the prompt shows: `job_id = queue.add_job(...)` and then `result = queue.get_result(...)`.
    *   However, the requirement "Jobs should be processed in FIFO order" implies that there's a processing mechanism.
    *   Let's look at the requirements again.
        *   `add_job`: adds to queue.
        *   `get_result`: retrieves result.
    *   If the jobs aren't automatically processed by a background thread in this simple implementation, I need a way to "process" them manually or simulate processing.
    *   Wait, the prompt doesned't specify a `process_next_job()` method, but it says "Jobs should be processed in FIFO order". Usually, in these coding tasks, if a method isn't explicitly required in the signature but a behavior is described, I should provide a way for that behavior to occur.
    *   Let's look at the prompt again: `queue.add_job(...)` -> `queue.get_result(...)`.
    *   To make `get_result` work, the job must be "processed" at some point.
    *   Perhaps I should include a private/internal method or a method `process_jobs()` to move items from the queue to a results dictionary.
    *   Or, perhaps the user expects `get_result` to trigger processing if it's not done yet? No, that violates FIFO if multiple results are requested.
    *   Let's refine the design:
        *   `self.queue`: A deque of tuples `(job_id, data)`.
        *   `self.results`: A dictionary `{job_id: result_data}`.
        *   `self.processed_jobs`: A set or just check the results dict.
        *   I need a way to "process". I'll add a `process_next_job` method or simply a `process_all_jobs` method to make the logic flow work, but I must ensure `add_job` and `get_result` are there.

    *   *Self-correction*: The prompt doesn't ask for a `process` method in the signature. But it says "Jobs should be processed in FIFO order".
    *   If I don't implement a processing mechanism, `get_result` will always return `None` (or an error) because nothing happened to the data in the queue.
    *   Maybe I should implement a simple `process_jobs` method internally or as a public method to demonstrate the FIFO requirement.
    *   Actually, a standard way to interpret this is: `add_job` puts it in a queue, and there's an implicit (or explicit) processing step. Since the user didn't define the `process` method in the prompt's "Requirements" list but mentioned the requirement "Jobs should be processed in FIFO", I will provide a `process_jobs` method to satisfy the FIFO requirement.

    *   *Revised Plan*:
        1. `collections.deque` for the queue.
        2. `dict` for results.
        3. `add_job`: append to deque.
        4. `process_jobs`: pop from left of deque, do something (mock processing), put in results.
        5. `get_result`: return from results.

    *   Actually, looking at the example usage:
        `job_id = queue.add_job("job1", {"task": "process_data"})`
        `# After processing...`
        `result = queue.get_result("job1")`
    *   The comment `# After processing...` implies that processing happens outside the `add_job` call (maybe in a separate thread or a separate call).
    *   Therefore, I need a way to "complete" a job.
    *   I'll add a `process_next_job` method to the class so the user can trigger the processing, satisfying the FIFO requirement.

    ```python
    from collections import deque
    from typing import Dict, Optional

    class JobQueue:
        def __init__(self):
            self.queue = deque()
            self.results = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self.queue.append((job_id, data))
            return job_id

        def process_next_job(self):
            if self.queue:
                job_id, data = self.queue.popleft()
                # Simulate processing
                result = {"status": "completed", "original_data": data}
                self.results[job_id] = result

        def get_result(self, job_id: str) -> dict | None:
            return self.results.get(job_id)
    ```

    *   Wait, if I only provide `add_job` and `get_result` as required, how does the user actually "process" the job to fulfill the "processed in FIFO order" requirement?
    *   Maybe the requirement "Jobs should be processed in FIFO order" refers to the internal logic of how the queue is drained.
    *   I will include a `process_next_job` method to make it functional, as it's the only way to move a job from "queue" to "result".

    *   Actually, I'll just make sure the queue logic uses a deque (FIFO).

    *   *Refined Class*:
        - `self._queue`: deque of `(job_id, data)`
        - `self._results`: dict `job_id -> result`
        - `add_job`: adds to deque, returns id.
        - `process_next_job`: pops from left, puts in dict.
        - `get_result`: returns from dict.

    *   Requirement 1: `add_job`, `get_result`. (Checked )
    *   Requirement 2: FIFO. ( Checked by using `deque.popleft()`)
    *   Requirement 3: Store jobs until processed. ( Checked )
    *   Requirement 4: Unique job_id. ( Checked - assumed input is unique, or I could generate them, but the signature says `job_id` is passed in).

    Wait, the signature is `add_job(job_id: str, data: dict) -> str`. This implies the user *provides* the `job_id`. The requirement says "Each job has a unique job_id that is returned when added". This is slightly contradictory if the user provides it. Usually, if the user provides it, it's assumed unique. If the system generates it, the signature would be `add_job(data: dict) -> str`.

    Looking at the example: `queue.add_job("job1", ...)` -> The user provides `"job1"`.
    So the system returns the same string.

    I will write the code now.

    *Self-Correction during coding*: To ensure "processed in FIFO", I'll provide a `process_next_job` method.

    ```python
    from collections import deque
    from typing import Dict, Optional, Any

    class JobQueue:
        def __init__(self):
            self._queue: deque[tuple[str, dict]]] = deque()
            self._results: Dict[str, dict[str, Any]]] = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self._queue.append((job_id, data))
            return job_id

        def process_next_job(self) -> None:
            """Processes the next job in the FIFO queue."""
            if self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing logic
                self._results[job_id] = {"status": "success", "data": data}

        def get_result(self, job_id: str) -> dict | None:
            return self._results.get(job_id)
    ```

    Wait, the prompt doesn't ask for `process_next_job`. It just says "Jobs should be processed in FIFO". If I don't include a way to process them, the code is useless. I'll include it.

    Wait, I should check if `get_result` should be the thing that triggers processing? No, that would break FIFO if someone calls `get_result` for a later job while an earlier one is still "pending".

    I'll stick to the required methods and add a processing method to make the class functional.

    Actually, I'll check the prompt again. "Write only the Python code, no explanations."

    Final structure:
    - Class `JobQueue`
    - `add_job`
    - `process_next_job` (added to satisfy FIFO requirement)
    - `get_result`

    Let's refine the return type for `get_result`. `dict | None`.

    Wait, should I use `threading`? The prompt says "basic job queue". Usually, "basic" means no threading unless specified.

    One more thing: "The queue should store jobs internally until they are processed". This is handled by the deque.

    Final code plan:
    ```python
    from collections import deque
    from typing import Dict, Optional, Any

2    class JobQueue:
        def __init__(self):
            self._queue: deque[tuple[str, dict]]] = deque()
            self._results: Dict[str, dict[str, Any]]] = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self._queue.append((job_id, data))
            return job_id

        def process_next_job(self) -> None:
            """Processes the next job in the FIFO queue."""
            if self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing the data
                self._results[job_id] = {"result": f"Processed {data.get('task')}"}

        def get_result(self, job_id: str) -> dict | None:
            return self._results.get(job_id)
    ```

    Wait, the prompt says "Write only the Python code". I will provide the simplest working version.

    One detail: `dict | None` requires Python 3.10+. I'll assume it's fine or use `Optional[dict]`. The prompt used `dict | None`, so I will use that syntax.

    Wait, if the user only calls `add_job` and `get_result`, and I don't provide a `process` method, how does the job get processed?
    Ah, I'll implement a `process_all` or `process_next` method.

    Actually, what if "processed in FIFO" means I should provide a way to process them? Yes.

    One alternative: `get_result` checks if the job is done. If not, it processes the queue until that `job_id` is reached? No, that's not FIFO order for the whole system, that's "process until this specific one is done".

    I'll stick to the `process_next_job` method.

    Final check on requirements:
    1. `JobQueue` class with `add_job` and `get_result`. (Yes)
    2. FIFO order. (Yes, deque + popleft)
    3. Store jobs until processed. (Yes, deque)
    4. Unique `job_id`. (Yes, passed in)

    Wait, the prompt says `job_id` is returned when added.
    `return job_id`. (Yes)

    One edge case: what if `get_result` is called before processing? It returns `None`. This is correct.
</reasoning_content>

<content>
```python
from collections import deque
from typing import Dict, Any

class JobQueue:
    def __init__(self):
        # Queue stores tuples of (job_id, data) to maintain FIFO order
        self._queue: deque[tuple[str, dict]]] = deque()
        # Results dictionary stores completed jobs
        self._results: Dict[str, dict[str, Any]]] = {}

    def add_job(self, job_id: str, data: dict) -> str:
        """Adds a job to the queue and returns the job_id."""
        self._queue.append((job_id, data))
        return job_id

    def process_next_job(self) -> None:
        """
        Processes the next job in the queue (FIFO).
        This method fulfills the requirement that jobs are processed in order.
        """
        if self._queue:
            job_id, data = self._queue.popleft()
            # Simulate processing logic
            self._results[job_id] = {
                "status": "completed",
                "result": data.get("task", "no_task_specified")
            }

    def get_result(self, job_id: str) -> dict | None:
        """Returns the result of a completed job, or None if not yet processed."""
        return self._results.get(job_id)
```
</content>