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# Python Module
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Core Python module interface for jupyterlab-visualpython, providing extension discovery and version management for JupyterLab integration.
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## Capabilities
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### Extension Discovery
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Provides JupyterLab with extension path information for proper installation and loading.
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```python { .api }
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def _jupyter_labextension_paths() -> List[Dict[str, str]];
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```
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**Description**: Returns a list containing extension path configuration for JupyterLab extension discovery. Called automatically by JupyterLab during extension loading process.
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**Returns**: 
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- `List[Dict[str, str]]`: List with single dictionary containing:
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  - `'src'`: Source path to extension assets
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  - `'dest'`: Destination identifier for extension
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**Usage Example**:
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```python
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import visualpython
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# Called automatically by JupyterLab
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paths = visualpython._jupyter_labextension_paths()
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# Returns: [{'src': 'labextension', 'dest': 'jupyterlab-visualpython'}]
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```
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### Version Information
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Module version identifier following semantic versioning.
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```python { .api }
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__version__: str
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```
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**Description**: String constant containing the current version of the visualpython module.
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**Value**: `"0.1.0"`
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**Usage Example**:
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```python
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import visualpython
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print(f"Visual Python version: {visualpython.__version__}")
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# Output: Visual Python version: 0.1.0
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```
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## Module Structure
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### Import Behavior
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The module attempts to import version information from `_version.py` and falls back to "dev" if unavailable:
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```python
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try:
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    from ._version import __version__
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except ImportError:
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    import warnings
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    warnings.warn("Could not determine version", UserWarning)
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    __version__ = "dev"
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```
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### Module Files
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- **`__init__.py`**: Main module file with public API
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- **`_version.py`**: Version definition file
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## Installation Integration
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The module integrates with pip and JupyterLab through:
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1. **Pip Installation**: Package installed via `pip install jupyterlab-visualpython`
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2. **Extension Discovery**: JupyterLab calls `_jupyter_labextension_paths()` to locate extension
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3. **Asset Loading**: Extension assets loaded from specified paths
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4. **UI Integration**: Visual Python interface becomes available in JupyterLab
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## Error Handling
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The module handles version import failures gracefully by:
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- Catching `ImportError` when `_version.py` is unavailable
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- Issuing a warning about version determination failure
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- Falling back to "dev" version identifier
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- Continuing normal operation despite version import issues