# libtmux._internal.query_list.PKRequiredException

- **Module:** libtmux._internal.query_list
- **Package:** libtmux
- **Language:** Python
- **Kind:** exception
- **Source:** https://github.com/tmux-python/libtmux/blob/9fdd083a8181a827889337b63cd4e6daea661a8c/src/libtmux/_internal/query_list.py#L317
- **Page:** https://libtmux.org/en/py/latest/reference/libtmux-_internal-query_list-pkrequiredexception/

Raised when :meth:`QueryList.items` is called without a primary key.

``items()`` pairs each entry with a key, and the list has no opinion about
which field that should be. Set ``pk_key`` on the list before calling it.

## Members

- `__init__` (method)