Registration

__init__(registry, key, metadata) -> None

def __init__(self, registry: Registry, key: MetricKey, metadata: Metadata) -> None:
    self._registry = registry
    self._key = key
    self._metadata = metadata

remove() -> None

def remove(self) -> None:
    if self._registry.get(self._key) is self._metadata:
        del self._registry[self._key]