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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):


        start = ''
        tsmatch = compile(r'/(\d+)-').search(imageUrl)
        if tsmatch:
            start = datetime.utcfromtimestamp(int(tsmatch.group(1))).strftime("%Y-%m-%d")
        else:
            # There were only chapter 1, page 4 and 5 not matching when writing
            # this...
            start = '2015-04-11x'
        return start + "-" + pageUrl.rsplit('/', 1)[-1]