Make startRecord a variable

sru/almasru.py

@@ -82,19 +82,19 @@ class RecordRetriever:
         :raises SruDiagnostics: if SRU returns an error
         """
 
-        sru_url = self._create_url(alma_query)
+        startrecord = '0'
 
-        response = request.urlopen(sru_url).read()
-        sru_xml = fromstring(response)
+        sru_url = self._create_url(alma_query, startrecord)
+        sru_xml = self._response_to_xml(sru_url)
 
         self._raise_errors_single_records(sru_xml)
 
         xml_list = self._extract_marc_xml(sru_xml)
         return xml_list[0]
 
-    def _create_url(self, alma_query: str) -> str:
+    def _create_url(self, alma_query: str, startrecord: str) -> str:
 
-        self.url_query['startRecord'] = '0'
+        self.url_query['startRecord'] = startrecord
         self.url_query['maximumRecords'] = '1'
         self.url_query['query'] = alma_query
         url_query_string = parse.urlencode(self.url_query)