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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 get_by_enclosures(self, enclosure_urls):
 """ Get bitlove data for a list of enclosure URLs """


        # prepare URLs
        enclosure_urls = map(str.strip, enclosure_urls)
        enclosure_urls = filter(None, enclosure_urls)

        return BitloveResponse(self.opener, enclosure_urls)