another fix

remote_dumps/quagga_aggregate.py

@@ -22,7 +22,7 @@ def dedup(asn_path):
 def find_common_suffixes(prefix_asn_paths, common_asn_suffix):
     for prefix, asn_lists in prefix_asn_paths.items():
         asn_lists = [dedup(asn_list.split(' ')) for asn_list in asn_lists] # preprocess
-        asn_lists = [asn_list for asn_list in asn_lists if asn_list != []] # this very rarely happens in dumps
+        asn_lists = [asn_list for asn_list in asn_lists if asn_list != [] and asn_list != ['']] # this very rarely happens in dumps
         asn_lists.sort(key = len)
         cur_asn_suffix = asn_lists[0] # represents the common sub-path (from the end) of asns to a prefix
         for asn_list in asn_lists[1:]: