--- sympy-sympy-1.7/sympy/printing/preview.py.orig	2020-11-29 04:02:22.000000000 -0700
+++ sympy-sympy-1.7/sympy/printing/preview.py	2020-12-10 10:55:53.290413553 -0700
@@ -32,8 +32,8 @@ def _run_pyglet(fname, fmt):
     from pyglet.window import key
 
     if fmt == "png":
-        from pyglet.image.codecs.png import PNGImageDecoder
-        img = image.load(fname, decoder=PNGImageDecoder())
+        from pyglet.image.codecs.pil import PILImageDecoder
+        img = image.load(fname, decoder=PILImageDecoder())
     else:
         raise ValueError("pyglet preview works only for 'png' files.")