diff --git a/src/music_storage/db_reader/extern_library.rs b/src/music_storage/db_reader/extern_library.rs
index ffe0711..fa5cd4e 100644
--- a/src/music_storage/db_reader/extern_library.rs
+++ b/src/music_storage/db_reader/extern_library.rs
@@ -1,9 +1,12 @@
 use std::path::PathBuf;
 
+use crate::music_storage::library::Song;
+
 
 pub trait ExternalLibrary {
-    fn from_file(&mut self, file: &PathBuf) -> Self;
+    fn from_file(file: &PathBuf) -> Self;
     fn write(&self) {
         unimplemented!();
     }
+    fn to_songs(&self) -> Vec<Song>;
 }
\ No newline at end of file