docs: def convert_uniprot_to_entrez(self, uniprot):
          """Convert Uniprot Id to Entrez Id"""
          # Submit request to NCBI eutils/Gene Database
          server = "http://eutils.ncbi.nlm.nih.gov/entrez/eutils/esearch.fcgi?" + self.options + "&db=gene&term={0}".format(
              uniprot)
          r = requests.get(server, headers={"Content-Type": "text/xml"})
          if not r.ok:
              r.raise_for_status()
              sys.exit()
          # Process Request
          response = r.text
          info = xmltodict.parse(response)
          geneId = info['eSearchResult']['IdList']['Id']
          # check to see if more than one result is returned
          # if you have more than more result then check which Entrez Id returns the same uniprot Id entered.
          if len(geneId) > 1:
              for x in geneId:
                  c = self.convert_entrez_to_uniprot(x)
                  c = c.lower()
                  u = uniprot.lower()
                  if c == u:
                      return x
          else:
              return geneId