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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 from_map(map_key):
    'use resolved map as image'
    image_id = subprocess.check_output(['plash', 'map',
                                        map_key]).decode().strip('\n')
    if not image_id:
        raise MapDoesNotExist('map {} not found'.format(repr(map_key)))
    return hint('image', image_id)