diff --git a/karaokatalog/Library.py b/karaokatalog/Library.py
index 6d22b7a..c5c144b 100644
--- a/karaokatalog/Library.py
+++ b/karaokatalog/Library.py
@@ -1,5 +1,6 @@
 from collections.abc import Sequence
 from dataclasses import dataclass
+from functools import cached_property
 from pathlib import Path
 from typing import Self
 
@@ -31,3 +32,14 @@ class Library:
         )
 
         return cls(songs, unparseable_song_txts)
+
+    @cached_property
+    def songs_in_unique_dirs(self) -> Sequence[Song]:
+        """
+        Sometimes, more than one song can share the same base directory in a library (this usually happens when there are variants
+        of the song which share the same audio file).
+
+        For deduplication, it is helpful to assume every song is in its own directory. This returns a sequence of songs filtered so
+        that there are no two songs sharing the same base dir. This filtering is done arbitrarily.
+        """
+        raise NotImplementedError()  # TODO Implement