change variable name

palindrome.py

@@ -5,15 +5,15 @@
 def isPalindrome(word):
     end = len(word)
     start = 0
-    foo = True
+    retval = True
     while start < end+1:
         left = word[start]
         right = word[end-1]
         if left != right:
-            foo = False
+            retval = False
             break
         start += 1
         end -= 1
-    return foo
+    return retval
 
 print isPalindrome("wwaabbaawwz")