def guide_with_numbers(guide):
    """Supply an instance of Guide with some defined numbers."""
    values = (
        ("i", "I"),
        ("v", "V"),
        ("x", "X"),
        ("foo", "L"),
        ("bar", "L"),
        ("foobar", "L"),
        ("Glob", "M"),
    )
    for name, value in values:
        guide._parse_number_definition([name, "is", value])
    return guide