diff --git a/dups.py b/dups.py
index 01ca0ff..30682e5 100644
--- a/dups.py
+++ b/dups.py
@@ -218,7 +218,7 @@ class Duplicates:
                 self.overall_dup_cnt += len(self.dups_to_process[hash])
                 self.overall_dup_sets += 1
                 for el in self.dups_to_process[hash]:
-                    if re.search( '\d{4}/\d{8}', el.d):
+                    if re.search( r'\d{4}/\d{8}', el.d):
                         self.preferred_file[hash] = el.id
             # by here we have only 2 files, with the same name, different path (ask per path)
             elif d1 != self.dups_to_process[hash][0].d:
@@ -226,9 +226,9 @@ class Duplicates:
                     self.overall_dup_cnt += dup_cnt
                     self.overall_dup_sets += 1
                     self.per_path_dups.append( DupPathRow( dup_cnt, d1, d2, did1, did2, hashes ) )
-                    if re.search( '\d{4}/\d{8}', d1):
+                    if re.search( r'\d{4}/\d{8}', d1):
                         self.preferred_path[did1]=1
-                    if re.search( '\d{4}/\d{8}', d2):
+                    if re.search( r'\d{4}/\d{8}', d2):
                         self.preferred_path[did2]=1
                     dup_cnt=1
                 d1 = self.dups_to_process[hash][0].d