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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 as_xml_index(self, basename="/tmp/sitemap.xml"):
 """Return a string of the index for a large list that is split. All we need to do is determine the number of component sitemaps will be is and generate their URIs based on a pattern. Q - should there be a flag to select generation of each component sitemap in order to calculate the md5sum? Q - what timestamp should be used? """

        num_parts = self.requires_multifile()
        if (not num_parts):
            raise ListBaseIndexError(
                "Request for sitemapindex for list with only %d entries when max_sitemap_entries is set to %s" %
                (len(self), str(
                    self.max_sitemap_entries)))
        index = ListBase()
        index.sitemapindex = True
        index.capability_name = self.capability_name
        index.default_capability()
        for n in range(num_parts):
            r = Resource(uri=self.part_name(basename, n))
            index.add(r)
        return(index.as_xml())