Simplify writing file chunks
Simplify writing file chunks

A plain loop is easier to follow than chained generators consumed by
a helper function, and reduces the number of objects being passed around
just to download a file.

pradyunsg/pip,xavfernandez/pip,sbidoul/pip,pradyunsg/pip,pypa/pip,pypa/pip,xavfernandez/pip,xavfernandez/pip,sbidoul/pip,pfmoore/pip,pfmoore/pip