# TypeError: _mock_children() got an unexpected keyword argument 'autospec'
  File ".../unittest/mock.py", line ..., in __init__
    self._mock_children = {}

- **ID:** `python/unittest-mock-autospec-call-arg`
- **Domain:** python
- **Category:** type_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

A custom Mock subclass overrides __init__ without forwarding **kwargs to super().__init__, so attributes like autospec/spec_set are silently dropped or cause errors when combined with `create_autospec`.

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |

## Workarounds

1. **** (95% success)
   ```
   from unittest.mock import Mock

class MyMock(Mock):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
   ```
2. **** (92% success)
   ```
   from unittest.mock import create_autospec

mock_client = create_autospec(MyClient, instance=True)
mock_client.fetch.return_value = {"ok": True}
   ```

## Dead Ends

- **** — Loses signature checking; tests pass with typos in method names, defeating the purpose. (75% fail)
- **** — The subclass __init__ swallows the kwarg, so autospec is not applied. (80% fail)