Session 3: paperless guesses in boxes.py, warmup.py, exit ticket

boxes.py

@@ -1,32 +1,38 @@
 # BOXES
 #
 # Do NOT run this yet!
-# First, guess what each program prints. Write your guesses on your paper.
+# Read each program. Guess what it prints.
+# Type your guess after "My guess:" (it is a comment, so Python ignores it).
 # Then run it and check.
 
 
 print("--- Program 1 ---")
 pet = "cat"
 print(pet)
+# My guess: 
 
 
 print("--- Program 2 ---")
 pet = "cat"
 print("pet")
+# My guess: 
 
 
 print("--- Program 3 ---")
 pet = "cat"
 pet = "dog"
 print(pet)
+# My guess: 
 
 
 print("--- Program 4 ---")
 x = 5
 x = 7
 print(x)
+# My guess: 
 
 
 print("--- Program 5 ---")
 name = "Sam"
 print("Hi, Sam " + name)
+# My guess: