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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 _determine_selected_stencil(stencil_set, stencil_definition):
 """Determine appropriate stencil name for stencil definition. Given a fastfood.json stencil definition with a stencil set, figure out what the name of the stencil within the set should be, or use the default """

    if 'stencil' not in stencil_definition:
        selected_stencil_name = stencil_set.manifest.get('default_stencil')
    else:
        selected_stencil_name = stencil_definition.get('stencil')

    if not selected_stencil_name:
        raise ValueError("No stencil name, within stencil set %s, specified."
                         % stencil_definition['name'])

    return selected_stencil_name