fix collision detection issue

module/block.py

@@ -11,6 +11,12 @@ class Block:
         self.x = x
         self.y = y
 
+    def get_screen_x(self):
+        return self.x * 20
+
+    def get_screen_y(self):
+        return self.y * 20
+
 
 class GrassBlock(Block):
     id = 'grass'