change groups to group to return tld as string instead of tuple

src/convert-to-parquet/convert-to-parquet.py

@@ -33,7 +33,7 @@ def parse_line(line):
 
         grp = re.match(r'(?:/data/user(?:/home)?/|/data/project/|/scratch/)([^/]+)',path)
         if grp:
-            tld = grp.groups(1)
+            tld = grp.group(1)
         else:
             tld = None