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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_media_list_by_selector( self, media_selector, media_attribute="src" ):
 """Return a list of media."""

        page_url = urlparse.urlparse(self.uri)
        return [
            mediafile.get_instance(
                urlparse.urljoin(
                    "%s://%s" % (
                        page_url.scheme,
                        page_url.netloc
                    ),
                    urlparse.urlparse(
                        media.attrib[media_attribute],
                        scheme="http"
                    ).geturl()
                )
            )
            for media in self.parsedpage.get_nodes_by_selector(media_selector)
        ]