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

# docker

# `prefect.testing.docker`

## Functions

### `capture_builders` <sup><a href="https://github.com/PrefectHQ/prefect/blob/main/src/prefect/testing/docker.py#L9" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python theme={null}
capture_builders() -> Generator[list[ImageBuilder], None, None]
```

Captures any instances of ImageBuilder created while this context is active