[gnome-music] coregrilo: Add docstrings to wrapper function

[Jean Felder <jfelder src gnome org>]

commit 545c6ef3f6fdc0cd6c0833bb60fa9a677f937b48
Author: Chinmay Gurjar <chnmgurjar gmail com>
Date:   Fri Jul 3 15:22:30 2020 +0530

    coregrilo: Add docstrings to wrapper function

 gnomemusic/coregrilo.py | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
---
diff --git a/gnomemusic/coregrilo.py b/gnomemusic/coregrilo.py
index 33957878..c89b83e0 100644
--- a/gnomemusic/coregrilo.py
+++ b/gnomemusic/coregrilo.py
@@ -161,14 +161,30 @@ class CoreGrilo(GObject.GObject):
         self._search_wrappers.pop(source.props.source_id, None)
 
     def get_artist_albums(self, media, filter_model):
+        """Get all album by an artist
+
+        :param Grl.Media media: A Grilo Media item that represents Artist
+        :param Gfm.FilterListModel filter_model: The model to fill
+        """
         source = media.get_source()
         self._wrappers[source].get_artist_albums(media, filter_model)
 
     def get_album_discs(self, media, disc_model):
+        """Get all discs from an album
+
+        :param Grl.Media media: A Grilo Media item that represents Album
+        :param Gfm.SortListModel disc_model: The model to fill
+        """
         source = media.get_source()
         self._wrappers[source].get_album_discs(media, disc_model)
 
     def populate_album_disc_songs(self, media, discnr, callback):
+        """Get all songs from an album disc
+
+        :param Grl.Media media: A Grilo Media item that represents Album
+        :param int discnr: The disc number
+        :param callback: The callback to call for every song added
+        """
         source = media.get_source()
         self._wrappers[source].populate_album_disc_songs(
             media, discnr, callback)