def METHOD_NAME(store, dataset, snapshot):
    # Get metadata for a snapshot (hexsha)
    repo = pygit2.Repository(store.get_dataset_path(dataset))
    commit, _ = repo.resolve_refish(snapshot)
    hexsha = commit.hex
    created = commit.commit_time
    tree = commit.tree_id.hex
    return {'id': '{}:{}'.format(dataset, snapshot), 'tag': snapshot, 'hexsha': hexsha, 'created': created, 'tree': tree}