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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 check_scrapers():
 """Check for duplicate scraper class names."""

    d = {}
    for scraperclass in _scraperclasses:
        name = scraperclass.getName().lower()
        if name in d:
            name1 = scraperclass.getName()
            name2 = d[name].getName()
            raise ValueError('duplicate scrapers %s and %s found' % (name1, name2))
        d[name] = scraperclass