Have you seen Dumbo?
Described as:
Dumbo is a project that allows you to easily write and run Hadoop programs in Python (it’s named after Disney’s flying circus elephant, since the logo of Hadoop is an elephant and Python was named after the BBC series “Monty Python’s Flying Circus”). More generally, Dumbo can be considered to be a convenient Python API for writing MapReduce programs.
I ran across DAG jobs and mapredtest on the Dumbo blog. Seeing DAG meant I had to run the reference down so here we are. 😉
The use of DAGs (directed acyclic graphs) with text representation systems have been studied by Michael Sperberg-McQueen and Claus Huitfeld for many years. DAGs are thought to be useful for some cases of overlapping markup.
I remain unconvinced by the DAG approach.