Updated koans from source.

koans/about_iteration.rb

@@ -78,13 +78,26 @@ class AboutIteration < EdgeCase::Koan
     assert_equal __, result
 
     # Files act like a collection of lines
-    upcase_lines = File.open("example_file.txt") do |file|
-      file.map { |line| line.strip.upcase }
+    File.open("example_file.txt") do |file|
+      upcase_lines = file.map { |line| line.strip.upcase }
+      assert_equal __, upcase_lines
     end
-    assert_equal __, upcase_lines
 
     # NOTE: You can create your own collections that work with each,
     # map, select, etc.
   end
 
+  # Bonus Question:  In the previous koan, we saw the construct:
+  #
+  #   File.open(filename) do |file|
+  #     # code to read 'file'
+  #   end
+  #
+  # Why did we do it that way instead of the following?
+  #
+  #   file = File.open(filename)
+  #   # code to read 'file'
+  #
+  # When you get to the "AboutSandwichCode" koan, recheck your answer.
+
 end