Bag.map_partitions: simplify dsk build
Bag.map_partitions: simplify dsk build

mraspaud/dask,gameduell/dask,cowlicks/dask,blaze/dask,cpcloud/dask,ContinuumIO/dask,jakirkham/dask,mraspaud/dask,jakirkham/dask,chrisbarber/dask,ContinuumIO/dask,mrocklin/dask,dask/dask,dask/dask,mrocklin/dask,blaze/dask,jcrist/dask,jcrist/dask,mikegraham/dask