whitespace fixes

unit4/policy-by-thrun.py

@@ -1,11 +1,11 @@
 # ----------
 # User Instructions:
-# 
+#
 # Create a function optimum_policy() that returns
 # a grid which shows the optimum policy for robot
 # motion. This means there should be an optimum
 # direction associated with each navigable cell.
-# 
+#
 # un-navigable cells must contain an empty string
 # WITH a space, as shown in the previous video.
 # Don't forget to mark the goal with a *

unit4/print_path.py

@@ -3,15 +3,15 @@
 #
 # Modify the the search function so that it returns
 # a shortest path as follows:
-# 
+#
 # [['>', 'v', ' ', ' ', ' ', ' '],
 #  [' ', '>', '>', '>', '>', 'v'],
 #  [' ', ' ', ' ', ' ', ' ', 'v'],
 #  [' ', ' ', ' ', ' ', ' ', 'v'],
 #  [' ', ' ', ' ', ' ', ' ', '*']]
 #
-# Where '>', '<', '^', and 'v' refer to right, left, 
-# up, and down motions. NOTE: the 'v' should be 
+# Where '>', '<', '^', and 'v' refer to right, left,
+# up, and down motions. NOTE: the 'v' should be
 # lowercase.
 #
 # Your function should be able to do this for any