Description: compatibility with Python 3.9
 Python 3.9 removed the deprecated array.tostring method.
 Replacing it with array.tobytes.
Author: Sascha Steinbiss
Applied-Upstream: https://github.com/drj11/pypng/commit/fe9c973c5e92f24746dfa1be8796c14a2befec4f
Last-Update: 2020-10-27
--- a/code/test_png.py
+++ b/code/test_png.py
@@ -461,13 +461,13 @@
     def test_interlaced_array(self):
         """Reading an interlaced PNG yields each row as an array."""
         r = png.Reader(bytes=pngsuite.basi0g08)
-        list(r.read()[2])[0].tostring
+        list(r.read()[2])[0].tobytes
 
     def test_trns_array(self):
         """A type 2 PNG with tRNS chunk yields each row
         as an array (using asDirect)."""
         r = png.Reader(bytes=pngsuite.tbrn2c08)
-        list(r.asDirect()[2])[0].tostring
+        list(r.asDirect()[2])[0].tobytes
 
     def test_flat(self):
         """Test read_flat."""