Fix import script for use with multiprocessing
Fix import script for use with multiprocessing

multiprocessing.Pool requires the passed callable to be importable from
the module (for some reason) [1]. However, there is also no starmap
implemented on Pool so to get around this I've implemented it as a
callable class.

[1]
http://stackoverflow.com/questions/3288595/multiprocessing-using-pool-map-on-a-function-defined-in-a-class

RichardKnop/digitalmarketplace-api,alphagov/digitalmarketplace-api,mtekel/digitalmarketplace-api,alphagov/digitalmarketplace-api,mtekel/digitalmarketplace-api,mtekel/digitalmarketplace-api,mtekel/digitalmarketplace-api,RichardKnop/digitalmarketplace-api,alphagov/digitalmarketplace-api,RichardKnop/digitalmarketplace-api,RichardKnop/digitalmarketplace-api