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

# ConfigVar

> <a href="https://github.com/pixeltable/pixeltable/blob/main/pixeltable/config.py#L169" id="viewSource" target="_blank" rel="noopener noreferrer"><img src="https://img.shields.io/badge/View%20Source%20on%20Github-blue?logo=github&labelColor=gray" alt="View Source on GitHub" style={{ display: 'inline', margin: '0px' }} noZoom /></a>

# <span style={{ 'color': 'gray' }}>class</span>  pixeltable.ConfigVar

A reference to a database variable or secret, declared at module scope.

A declaration names the variable; the target it is applied to supplies the value.

Declare a variable and apply it to a column:

> > > MEDIA\_DEST = pxt.ConfigVar('media\_dest', pxt.URI)
> > > ...
> > > ...
> > > ... class Videos(TableModel, name='videos'):
> > > ...     clip = pxt.Column(value=..., destination=MEDIA\_DEST)

Code that runs on the target reads the bound value with `value()`.

## <span style={{ 'color': 'gray' }}>method</span>  value()

```python Signature theme={"theme":{"light":"light-plus","dark":"dark-plus"}}
value() -> ConfVarT
```

The bound value, converted to the declared type. Raises if the target has no binding for it.

**Examples:**

Read a secret from a udf, which runs on the target:

```python theme={"theme":{"light":"light-plus","dark":"dark-plus"}}
@pxt.udf
def summarize(text: str) -> str:
    return _call(text, key=API_KEY.value())
```