class ActiveFedora::Base

def add_file_datastream(file, opts={})
  label = opts.has_key?(:label) ? opts[:label] : ""
  ds = ActiveFedora::Datastream.new(:dsLabel => label, :controlGroup => 'M', :blob => file)
  opts.has_key?(:dsid) ? ds.dsid=(opts[:dsid]) : nil
  add_datastream(ds)
end