Rename MultiRecord to NotUnique, correct num_pages

sru/almasru.py

@@ -34,7 +34,7 @@ class NoRecord(SruException):
     pass
 
 
-class MultiRecord(SruException):
+class NotUnique(SruException):
     pass
 
 
@@ -112,7 +112,7 @@ class RecordRetriever:
         self._raise_error_no_match(num_recs)
         self._raise_error_sru(sru_xml)
 
-        num_pages = num_recs//10
+        num_pages = int(num_recs.text)//10
 
         xml_list = self._extract_marc_xml(sru_xml)
 
@@ -148,7 +148,7 @@ class RecordRetriever:
 
         if (num_recs is not None and
                 num_recs.text > '1'):
-            raise MultiRecord('More than one record found'
+            raise NotUnique('More than one record found'
                             'while exactly one was expected!')
 
     @staticmethod