# Sortable


A connection type that can be compared for priority ordering.


`Sortable=TypeVar(``"Sortable", bound=`<span class="st">`"Connection"``)`</span>


Any type substituted for [Sortable](Sortable.md#gdtest_complete_docstrings.Sortable) must be a [Connection](Connection.md#gdtest_complete_docstrings.Connection) subclass. This is used internally by the priority queue that schedules health checks: connections with the oldest last-used timestamp are checked first.


## Notes

The bound is [Connection](Connection.md#gdtest_complete_docstrings.Connection) rather than a protocol because the priority comparison depends on internal state (`_last_used`) that is not part of any public protocol.


## See Also

[Connection](Connection.md#gdtest_complete_docstrings.Connection)