anki: Use fetchpatch for python compatibilty patch

pkgs/games/anki/default.nix

@@ -4,6 +4,7 @@
 , lib
 , python
 , fetchurl
+, fetchpatch
 , lame
 , mplayer
 , libpulseaudio
@@ -53,7 +54,16 @@ buildPythonApplication rec {
     patches = [
       # Disable updated version check.
       ./no-version-check.patch
-      ./python-3.7-compat.patch
+
+      # This is needed to fix python 3.7 compatibilty, where the
+      # behaviour of `re.escape()` was changed in a way that it no
+      # longer escapes `%`. This patch detects this difference at
+      # runtime and makes anki work with any python version.
+      # Upstream PR: https://github.com/dae/anki/pull/266
+      (fetchpatch {
+        url = "https://github.com/dae/anki/commit/3d69aa9ce454a151ba75deafd7de117af2c7307d.patch";
+        sha256 = "0kf9gajhy0wcajp24xfia71z6gn1mc4vl37svvq4sqbhj3gigd0h";
+      })
     ];
 
     buildPhase = ''

pkgs/games/anki/python-3.7-compat.patch

@@ -1,23 +0,0 @@
-commit 3d69aa9ce454a151ba75deafd7de117af2c7307d
-Author: Alexey Lebedeff <binarin@binarin.ru>
-Date:   Fri Nov 30 10:44:39 2018 +0100
-
-    Fix searching for python 3.7
-    
-    3.7 introduced a change to `re.escape()`, which no longer escapes
-    `%`. By using `re.escape("%")` instead of a literal, we can detect
-    a proper form at runtime.
-
-diff --git a/anki/find.py b/anki/find.py
-index 48d0dd1..213216d 100644
---- a/anki/find.py
-+++ b/anki/find.py
-@@ -440,7 +440,7 @@ select distinct(n.id) from cards c, notes n where c.nid=n.id and """+preds
-             # nothing has that field
-             return
-         # gather nids
--        regex = re.escape(val).replace("_", ".").replace("\\%", ".*")
-+        regex = re.escape(val).replace("_", ".").replace(re.escape('%'), ".*")
-         nids = []
-         for (id,mid,flds) in self.col.db.execute("""
- select id, mid, flds from notes