Earning Points. Starwood's Preferred Guest program is fairly straightforward: the more nights you spend at participating hotels, the faster you'll earn a free night.
As seen in the EXECUTING phase, the map will write (using Mapper.Context.write()) its output into a circular in-memory buffer (MapTask.MapOutputBuffer). The size of this buffer is fixed and determined by the configuration parameter mapreduce.task.io.sort.mb (default: 100MB).
You need to create a class derived from MRjob and provide essential methods like mapper, combiner and reducer. Depending on what you want to do, you may need only a mapper or mapper and reducer or all of them. You should be able to successfully run the map-reduce using mrjob. Input to a mapper is a line and it's output is a (key, value) pair . In this case, it's output is (keyword, 1) pair.