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README.md

@@ -5,7 +5,9 @@ Comprehensive collection of well-known, and not so well-known, programming
 styles using a simple computational task, term frequency. All programs run 
 with the following command line:
 
-$ python tf-NN.py ../pride-and-prejudice.txt
+```bash
+python tf-NN.py ../pride-and-prejudice.txt
+```
 
 Explanations and historical context for all these styles can be found in the
 companion book [Exercises in Programming Style](http://www.amazon.com/Exercises-Programming-Style-Cristina-Videira/dp/1482227371/).