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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 css_class_cycler():
    '''
    Return a dictionary keyed by ``EventType`` abbreviations, whose values are an
    iterable or cycle of CSS class names.

    '''
    FMT = 'evt-{0}-{1}'.format
    return defaultdict(default_css_class_cycler, (
        (e.abbr, itertools.cycle((FMT(e.abbr, 'even'), FMT(e.abbr, 'odd'))))
        for e in EventType.objects.all()
    ))