Bigdata cluster compatible distributed predictive model I might be asking a dumb question but my question is can I write a python program (lets say a classifier) using some library that scales in hadoop (not only using a simple parallel processing).The reason I am confused is 
1)The scikit learn python codes don't scale in big data.
2)The spark mlib is written in scala and not in python.
3)Although h2o is open sourced I don't think it is written in python.
Spark does have a pretty good Python API, check out this tutorial.

For traditional Hadoop stack, take a look at mrjob, it lets you write MapReduce jobs in Python and run them on several platforms.