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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_pubmed_xml(self):
 """ Use a PubMed ID to retrieve PubMed metadata in XML form. """

        url = 'http://eutils.ncbi.nlm.nih.gov/entrez/eutils/' \
              'efetch.fcgi?db=pubmed&rettype=abstract&id={}' \
              .format(self.pmid)

        try:
            response = urlopen(url)
        except URLError:
            xml_dict = ''
        else:
            xml = response.read().decode()
            xml_dict = xmltodict.parse(xml)

        return xml_dict