These are integers and use of "is" with pygame-2 ignores input events.

https://bugs.gentoo.org/794211

See also: pygame-2.0.1/buildconfig/pygame-stubs/constants.pyi
--- a/pathological.py
+++ b/pathological.py
@@ -133,3 +133,3 @@
 	if colorkey is not None:
-		if colorkey is -1:
+		if colorkey == -1:
 			colorkey = image.get_at((0,0))
@@ -1395,6 +1395,6 @@
 			for event in pygame.event.get():
-				if event.type is QUIT:
+				if event.type == QUIT:
 					return -4
-				elif event.type is KEYDOWN:
-					if event.key is K_ESCAPE: return -3
+				elif event.type == KEYDOWN:
+					if event.key == K_ESCAPE: return -3
 					elif event.key == ord('n'): return 2
@@ -1419,3 +1419,3 @@
 
-				elif event.type is MOUSEBUTTONDOWN:
+				elif event.type == MOUSEBUTTONDOWN:
 					if self.paused:
@@ -1713,5 +1713,5 @@
 			for event in pygame.event.get():
-				if event.type is QUIT:
+				if event.type == QUIT:
 					return -2
-				elif event.type is KEYDOWN:
+				elif event.type == KEYDOWN:
 					if event.key == K_ESCAPE: return -1
@@ -1744,3 +1744,3 @@
 					return 1
-				elif event.type is MOUSEBUTTONDOWN:
+				elif event.type == MOUSEBUTTONDOWN:
 					return 1
@@ -1799,5 +1799,5 @@
 		for event in pygame.event.get():
-			if event.type is QUIT:
+			if event.type == QUIT:
 				return None
-			elif event.type is KEYUP:
+			elif event.type == KEYUP:
 				if event.key == K_LSHIFT:
@@ -1806,3 +1806,3 @@
 					shift_state &= ~KMOD_RSHIFT
-			elif event.type is KEYDOWN:
+			elif event.type == KEYDOWN:
 				if event.key == K_LSHIFT:
@@ -1994,3 +1994,3 @@
 			for event in pygame.event.get():
-				if event.type is QUIT:
+				if event.type == QUIT:
 					if self.curpage == 1:
@@ -1999,3 +1999,3 @@
 					return -2
-				elif event.type is KEYDOWN:
+				elif event.type == KEYDOWN:
 					if event.key == K_F2:
@@ -2032,3 +2032,3 @@
 					continue
-				elif event.type is MOUSEBUTTONDOWN:
+				elif event.type == MOUSEBUTTONDOWN:
 					if self.curpage == 1: