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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 entry_breadcrumbs(entry):
 """ Breadcrumbs for an Entry. """

    date = entry.publication_date
    if is_aware(date):
        date = localtime(date)
    return [year_crumb(date), month_crumb(date),
            day_crumb(date), Crumb(entry.title)]