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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def parse_images_output(out):
 """ Parses the output of the Docker CLI 'docker images'. Note this is currently incomplete and only returns the ids and tags of images, as the Docker CLI heavily modifies the output for human readability. The parent image id is also not available on the CLI, so a full API compatibility is not possible. :param out: CLI output. :type out: unicode | str :return: Parsed result. :rtype: list[dict] """

    line_iter = islice(out.splitlines(), 1, None)  # Skip header
    split_lines = (line.split() for line in line_iter)
    return [
        _summarize_tags(image_id, image_lines)
        for image_id, image_lines in groupby(sorted(split_lines, key=_get_image_id), key=_get_image_id)
    ]