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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 to construct meaningful image name."""

        parts, year, month, stripname = pageUrl.rsplit('/', 3)
        stripname = stripname.rsplit('.', 1)[0]
        parts, imagename = imageUrl.rsplit('/', 1)
        return '%s-%s-%s-%s' % (year, month, stripname, imagename)