> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mellea.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# mellea.formatters.granite.base.optional

> Context-manager helpers for gracefully handling optional import dependencies.

export const SidebarFix = () => <script dangerouslySetInnerHTML={{
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<SidebarFix />

Context-manager helpers for gracefully handling optional import dependencies.

Provides `import_optional`, a context manager that catches `ImportError` and
re-raises it with a human-readable install hint (e.g. `pip install <package>[extra]`),
and `nltk_check`, a variant tailored to NLTK data-download errors. Used by Granite
formatter modules that have optional third-party dependencies.

## Functions

<div className="w-full h-px bg-gray-200 dark:bg-gray-700 my-4" />

### <span className="ml-2 inline-flex items-center rounded-full px-2 py-1 text-[0.7rem] font-bold tracking-wide bg-[#3064E3]/20 text-[#1D4ED8]">FUNC</span> `import_optional` <sup><a href="https://github.com/generative-computing/mellea/blob/v0.6.0/mellea/formatters/granite/base/optional.py#L25" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python theme={null}
import_optional(extra_name: str)
```

Handle optional imports.

**Args:**

* `extra_name`: Package extra to suggest in the install hint
  (e.g. `pip install mellea[extra_name]`).

<div className="w-full h-px bg-gray-200 dark:bg-gray-700 my-4" />

### <span className="ml-2 inline-flex items-center rounded-full px-2 py-1 text-[0.7rem] font-bold tracking-wide bg-[#3064E3]/20 text-[#1D4ED8]">FUNC</span> `nltk_check` <sup><a href="https://github.com/generative-computing/mellea/blob/v0.6.0/mellea/formatters/granite/base/optional.py#L45" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python theme={null}
nltk_check(feature_name: str)
```

Variation on import\_optional for nltk.

**Args:**

* `feature_name`: Name of the feature that requires NLTK, used in the error message.

**Raises:**

* `ImportError`: If the `nltk` package is not installed or required
  NLTK data (e.g. `punkt_tab`) has not been downloaded,
  re-raised with a descriptive message and installation
  instructions.

<div className="w-full h-px bg-gray-200 dark:bg-gray-700 my-4" />