Test: work with ancient matplotlib

Author: dschwoerer

xbout/tests/test_animate.py

@@ -179,7 +179,9 @@ def test_animate_list_1d_default(self, create_test_file):
     def test_animate_list_1d_multiline(self, create_test_file):
         save_dir, ds = create_test_file
 
-        if matplotlib._version.version_tuple >= (3, 7):
+        if hasattr(
+            matplotlib._version, "version_tuple"
+        ) and matplotlib._version.version_tuple >= (3, 7):
             pytest.xfail("Broken with new matplotlib")
 
         animation = ds.isel(y=2, z=3).bout.animate_list(