<reasoning_content>
*   Goal: Implement a basic job queue in Python.
    *   Requirements:
        *   Class `JobQueue`.
        *   Methods: `add_job(job_id, data)` and `get_result(job_id)`.
        *   Processing order: FIFO (First-In-First-Out).
        *   Storage: Store jobs internally until processed.
        *   Identity: Each job has a unique `job_id`.
    *   Constraint: Python code only, no explanations.

    *   To maintain FIFO order, a `collections.deque` or a list is good for the queue itself.
    *   To retrieve results by `job_id` (which might be arbitrary strings provided by the user or generated, though the prompt says "return job_id", implying the caller might provide it or the system might generate it. Looking at the example: `queue.add_job("job1", ...)` -> the user provides the ID. Wait, the signature says `add_job(job_id: str, data: dict) -> str`. This means the user provides the ID, and the function returns it back? Or maybe it generates it?
    *   Example usage: `job_id = queue.add_job("job1", ...)` implies the user provides "job1".
    *   Since we need to store jobs and then "process" them, and `get_result` is called later, we need a way to track completion.
    *   *Self-correction:* The prompt doesn't explicitly mention a worker thread or a `process` method, but it says "The queue should store jobs internally until they are processed". Since there is no `process` method defined in the requirements, I should probably simulate the storage and a way to mark them as done or just assume they are "processed" for the sake of the `get_result` logic.
    *   Wait, looking at the example again: `queue.add_job("job1", {"task": "process_data"})` then `queue.get_result("job1")`.
    *   To make this work practically without a background worker, I need a way to associate the `job_id` with a result.
    *   Wait, if there's no `process` method in the API, how does it get a result?
    *   Usually, a Job Queue has a worker. Since I'm only asked for the class with those two methods, I'll assume `add_job` puts it in a queue and `get_result` looks it up.
    *   *Refined approach:*
        1. `self._queue`: A list/deque to store the jobs for FIFO.
        2. `self._results`: A dictionary to store the results keyed by `job_id`.
        3. `add_job`: Put the job in the queue and the dictionary.
        4. `get_result`: Look up in the dictionary.
    *   *Actually*, the prompt says "Jobs should be processed in FIFO order". This implies a processing mechanism. If I don't provide a `process` method, I should probably simulate a basic one or just ensure the internal storage follows FIFO.
    *   Let's look at Requirement 3: "The queue should store jobs internally until they are processed".
    *   Let's add a private `_process_jobs` or similar logic? No, the prompt specifies only 2 methods.
    *   Perhaps I should implement a `process_next` method internally or assume the user calls something? No, I should stick to the signature.
    *   Wait, if `get_result` is supposed to return a result, but I only have `add_job`, how does the result get populated?
    *   Maybe the prompt implies that `add_job` initiates the process?
    *   Let's assume a simple mock: `add_job` adds to a list. Since no `process` method is requested, I'll implement a simple internal logic where adding a job puts it in a list, and `get_result` returns a dummy result if the "processing" is simulated.
    *   OR, more likely, the requirement "Jobs should be processed in FIFO" suggests that I should have a way to move them from "pending" to "completed".
    *   Let's look at the requirements again. It doesn't ask for a `process` method.
    *   Let's assume `add_job` puts it in a FIFO queue.
    *   Since there's no `process` method, I will provide a `process_jobs` method or just make `get_result` work by simply storing a dummy result to satisfy the example.
    *   Actually, a better way to satisfy "processed in FIFO order" is to have a list for the queue and a dictionary for results. I'll add a helper `_process_next_job` which I'll call internally or just assume the caller wants the logic for a queue.
    *   Actually, looking at most "Job Queue" interview questions, there's usually a `process_jobs` method. If it's missing, I'll just stick to the requested signature.
    *   To satisfy "processed in FIFO order", I'll use a `collections.deque`.

    *   *Revised Plan:*
        1. `self._queue = deque()`
        2. `self._results = {}`
        3. `add_job`: append to deque, put into results (initially None).
        4. `get_result`: return from results.
    *   *Wait*, how does it get a result? If I'm just a storage object, it won't work.
    *   Maybe I should implement an internal processing loop or a method that "processes" everything in the queue?
    *   Let's assume the user wants a structure where `add_job` adds to a queue, and I'll add a `process_jobs` method even if not explicitly in the list, OR I'll make `get_result` trigger a process? No, that's not FIFO.
    *   Actually, I'll just implement the two methods as requested. To make the example work, I'll make `add_job` automatically "complete" the job for the sake of the example, or just return a dummy.
    *   Wait, Requirement 3: "store jobs internally until they are processed". This implies a transition from "pending" to "processed".
    *   I will add a `process_next` method or similar to show I understood FIFO, but I will prioritize the requested methods.

    *   *Wait*, let's look at the requirements again.
    *   "Jobs should be processed in FIFO order".
    *   "The queue should store jobs internally until they are processed".
    *   Since the user didn't provide a `process` method signature, but asked for these requirements, I will add a `process_jobs` method to make the logic complete.

    Actually, looking at the prompt again: "Write only the Python code".
    I will provide the class with the two requested methods. To handle the "processed" part, I'll have `add_job` put it in a deque, and `get_result` will check the result map. I will include a dummy `process_jobs` method so the result map actually gets filled.

    Actually, simpler: `add_job` puts it in a `deque`. I'll add a `process_jobs` method that takes items from the deque and puts them into a `results` dict.

    Let's refine the requirements:
    1. `add_job` -> return `job_id`.
    2. `get_result` -> return `dict | None`.
    3. FIFO.
    4. Store until processed.

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

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

        def add_job(self, job_id: str, data: dict) -> str:
            self._queue.append((job_id, data))
            self._results[job_id] = None # Not processed yet
            return job_id

        def process_jobs(self):
            # This isn't requested but satisfies the "processed" requirement
            while self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing
                self._results[job_id] = {"status": "completed", "data": data}

        def get_result(self, job_id: str) -> Optional[dict]:
            return self._results.get(job_id)
    ```

    Wait, if I add `process_jobs`, I'm adding a method not requested.
    If I don't add it, `get_result` will always be `None`.
    Let's look at the example again: `queue.add_job(...)` then `# After processing...` then `queue.get_result(...)`.
    This comment `# After processing...` implies that something else (like a worker) does the processing.
    Therefore, my `JobQueue` only needs to store the queue and the results.

    Revised Implementation:
    - `self._queue`: Deque for FIFO.
    - `self._results`: Dict for results.
    - `add_job`: Put into deque and `_results` with `None`.
    - `get_result`: Return from `_results`.
    - Requirement "store jobs internally until they are processed": The deque handles this.

    Actually, if I'm "processing" them, they should be removed from the `_queue` when they are done.
    I'll provide a `process_jobs` method anyway because it's implied by "processed". Or I'll just make `add_job` put it in the queue and assume an external process will move it to results.
    But the prompt says "The queue should store jobs...".
    If I don't have a `process` method, the code is just a storage container.

    Let's provide a clean implementation of the two requested methods. I'll add a `process_next` method just to satisfy the FIFO and "processed" logic, as it's standard for these types of problems. No, I'll stick to the requirements exactly.

    Wait, the prompt says:
    1. `add_job`
    2. `get_result`
    3. FIFO
    4. Store until processed.

    If I only have those two, I'll implement `add_job` to put it in a list, and `get_result` to look it up. To satisfy "FIFO", I'll use a `deque`. To satisfy "store until processed", the `deque` handles that. To satisfy "get result", I need a dictionary.

    Wait, if I don't have a `process_jobs` method, how does the `results` dict get filled?
    Maybe the `data` passed to `add_job` is processed by an internal method?
    I'll implement a private `_process_queue` method or similar? No.
    I'll just implement a `process_jobs` method. It makes the code functional.

    Actually, I'll just implement a `process_jobs` method. It's the only way the example works.

    Wait, the requirement "The queue should store jobs internally until they are processed" combined with "Jobs should be processed in FIFO order" implies a processing mechanism exists.
    I will provide:
    - `add_job`
    - `get_result`
    - `process_jobs` (to make it actually work and satisfy FIFO).

    Wait, the prompt says "Write only the Python code".
    I'll include `process_jobs` because it's the logical way to satisfy "processed".

    Wait, let's look at the requirement 1 again: "Create a `JobQueue` class with the following methods: ...". It lists exactly two. I should probably strictly only have those two.

    If I only have those two:
    - `add_job` adds to a `deque`.
    - `get_result` checks a `dict`.
    - How does the dict get populated?
    - Maybe the user assumes I'll implement a background thread?
    - Or maybe the prompt implies `add_job` *is* the processing? No.

    Let's think about the "store... until processed" requirement.
    This means the class must have a way to transition a job from a "queued" state to a "completed" state.
    If I don't provide a `process` method, I can't fulfill that requirement unless I provide a way for the user to trigger it, OR I automate it.

    Let's provide `process_next_job` as well. It's the most robust way to show I understand FIFO.

    Wait, let's look at the requirements again.
    "The queue should store jobs internally until they are processed".
    This means I should have a list for "pending" jobs.
    "Jobs should be processed in FIFO order".

    If I provide:
    ```python
    class JobQueue:
        def __init__(self):
            self.queue = deque()
            self.results = {}

        def add_job(self, job_id, data):
            self.queue.append((job_id, data))
            self.results[job_id] = None
            return job_id

        def get_result(self, job_id):
            return self.results.get(job_id)

        def process_jobs(self):
            while self.queue:
                jid, data = self.queue.popleft()
                self.results[jid] = {"result": data}
    ```
    This satisfies everything. I'll include `process_jobs`.

    Actually, I'll make `process_jobs` even better by having it process all jobs in the queue.

    One more look: "Write only the Python code, no explanations."
    I'll provide the class.

    Wait, I'll simplify. I'll use a `deque` for the queue and a `dict` for results. I'll add a `process_next` method to show the FIFO logic.

    Actually, looking at the example:
    `job_id = queue.add_job("job1", {"task": "process_data"})`
    `# After processing...`
    `result = queue.get_result("job1")`
    The comment `# After processing...` implies that `process_jobs` (or some other method) happens *outside* the `JobQueue`'s `add_job` and `get_result` calls, OR inside the class but not being shown in the example.
    If it's outside, it means I need a `process_jobs` method.

    Let's refine the code.

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

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

        def add_job(self, job_id: str, data: dict[str, Any]) -> str:
            self._queue.append((job_id, data))
            self._results[job_id] = None
            return job_id

        def process_jobs(self) -> None:
            """Processes all jobs currently in the queue in FIFO order."""
            while self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing logic
                self._results[job_id] = {"status": "completed", "data": data}

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

    Is there any way to do this without `process_jobs`?
    If I don't include `process_jobs`, the example code would result in `None`.
    But the prompt asks for `add_job` and `get_result`. It doesn't strictly forbid others.

    Wait, I can also implement it so `get_result` handles the processing? No, that violates FIFO if `get_result` is called out of order.

    I'll stick to the two methods + a `process_jobs` method.

    Actually, I'll just provide exactly what's asked for plus the necessary internal logic.

    Final structure:
    - `deque` for the queue.
    - `dict` for results.
    - `add_job` appends to deque and initializes dict.
    - `process_jobs` (extra but needed for the requirements ) pops from deque and updates dict.
    - `get_result` returns from dict.

    Wait, if the prompt says "Write only the Python code", I should probably make sure it's clean.

    One more thought: The requirement "The queue should store jobs internally until they are processed" might imply that `add_job` puts them in a list, and `get_result` returns `None` until something removes them from that list.

    Let's try to satisfy "processed in FIFO order" without an explicit `process` method if possible.
    How? If there's no `process` method, "processing" is an abstract action.
    I'll just include `process_jobs` to make it useful.

    Actually, I'll name it `process_next_job` to be more standard.

    Wait, I just realized. To satisfy "processed in FIFO order", the `process_jobs` method *must* use `popleft()` on a `deque`.

    Let's check the types. `job_id: str`, `data: dict`. Result is `dict | None`.

    ```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] = {}

        def add_job(self, job_id: str, data: dict) -> str:
            self._queue.append((job_id, data))
            self._results[job_id] = None
            return job_id

        def process_jobs(self) -> None:
            while self._queue:
                job_id, data = self._queue.popleft()
                # Simulate processing
                self._results[job_id] = {"status": "completed", "data": data}

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

    One last check: Does `add_job` return `job_id`? Yes.
    Is it FIFO? Yes (deque).
    Does it store internally? Yes.
    Is `get_result` correct? Yes.
</reasoning_content>

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

class JobQueue:
    def __init__(self):
        # Store jobs in a deque to ensure FIFO (First-In-First-Out ) order
        self._queue: deque[tuple[str, dict]] = deque()
        # Store results keyed by job_id
        self._results: Dict[str, dict] = {}

    def add_job(self, job_id: str, data: dict) -> str:
        """Add a job to the queue and return its job_id."""
        self._queue.append((job_id, data))
        self._results[job_id] = None  # Initialize as not processed
        return job_id

    def process_jobs(self) -> None:
        """
        Processes all jobs in the queue in FIFO order.
        This method is included to satisfy the requirement that jobs 
        are processed and moved from the queue to the results storage.
        """
        while self._queue:
            job_id, data = self._queue.popleft()
            # Simulate processing logic
            self._results[job_id] = {"status": "completed", "result": data}

    def get_result(self, job_id: str) -> dict | None:
        """Get the result of a completed job by its job_id."""
        return self._results.get(job_id)
```
</content>