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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 namer(cls, imageUrl, pageUrl):
 """Use page URL sequence which is apparently increasing."""

        num = pageUrl.split('/')[-1]
        ext = imageUrl.rsplit('.', 1)[1]
        return "thethinhline-%s.%s" % (num, ext)