def METHOD_NAME(repository, generate_directory):
    """Test the ``Repository.open`` method."""
    directory = generate_directory({'file_a': b'content_a', 'relative': {'file_b': b'content_b'}})
    with open(directory / 'file_a', 'rb') as handle:
        key_a = repository.put_object_from_filelike(handle)
    with open(directory / 'relative/file_b', 'rb') as handle:
        key_b = repository.put_object_from_filelike(handle)
    with repository.open(key_a) as handle:
        assert isinstance(handle, io.BufferedReader)
    with repository.open(key_a) as handle:
        assert handle.read() == b'content_a'
    with repository.open(key_b) as handle:
        assert handle.read() == b'content_b'