README.md in trackler-2.2.1.75

- old
+ new

@@ -56,9 +56,24 @@
 
 In general, all characters from the input should also be present in the transposed output.
 That means that if a column in the input text contains only spaces on its bottom-most row(s),
 the corresponding output row should contain the spaces in its right-most column(s).
 
+## Exception messages
+
+Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to
+indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not
+every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include
+a message.
+
+To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
+`raise Exception`, you shold write:
+
+```python
+raise Exception("Meaningful message indicating the source of the error")
+```
+
+
 ## Submitting Exercises
 
 Note that, when trying to submit an exercise, make sure the solution is in the `exercism/python/<exerciseName>` directory.
 
 For example, if you're submitting `bob.py` for the Bob exercise, the submit command would be something like `exercism submit <path_to_exercism_dir>/python/bob/bob.py`.