diff --git a/patacrep/content/include.py b/patacrep/content/include.py
index 275c30ba..0755c747 100644
--- a/patacrep/content/include.py
+++ b/patacrep/content/include.py
@@ -4,10 +4,11 @@ This plugin provides keyword 'include', used to include an external list of
 songs in JSON or YAML format.
 """
 
-import yaml
 import os
 import logging
 
+import yaml
+
 from patacrep.content import process_content, ContentError, ContentList, validate_parser_argument
 from patacrep import encoding, errors, files
 
diff --git a/test/test_content/datadir/songs/custom_list.yaml b/test/test_content/datadir/songs/custom_list.yaml
new file mode 100644
index 00000000..e32ff5c8
--- /dev/null
+++ b/test/test_content/datadir/songs/custom_list.yaml
@@ -0,0 +1,6 @@
+- sorted:
+    key: "@title"
+    content:
+      - exsong.sg
+      - chordpro.csg
+      - subdir/chordpro.csg
\ No newline at end of file