Programmatically create paperclip attachment

gistfile1.rb

1.9.2-p290 :002 > u = Upload.new
 => #<Upload id: nil, post_id: nil, created_at: nil, updated_at: nil, upload_file_name: nil, upload_content_type: nil, upload_file_size: nil, upload_updated_at: nil> 

1.9.2-p290 :004 > u.upload = File.open('/Users/Eric/Desktop/estimation grid.png')
 => #<File:/Users/Eric/Desktop/estimation grid.png> 

1.9.2-p290 :005 > u.save!
   (0.1ms)  begin transaction
  SQL (17.4ms)  INSERT INTO "uploads" ("created_at", "post_id", "updated_at", "upload_content_type", "upload_file_name", "upload_file_size", "upload_updated_at") VALUES (?, ?, ?, ?, ?, ?, ?)  [["created_at", Fri, 16 Mar 2012 16:13:46 UTC +00:00], ["post_id", nil], ["updated_at", Fri, 16 Mar 2012 16:13:46 UTC +00:00], ["upload_content_type", "image/png"], ["upload_file_name", "estimation_grid.png"], ["upload_file_size", 53079], ["upload_updated_at", Fri, 16 Mar 2012 16:13:43 UTC +00:00]]
   (23.8ms)  commit transaction
 => true 

##########

1.9.2-p290 :007 > Upload.create!(:upload => File.open('/Users/Eric/Desktop/estimation grid.png'))
   (0.1ms)  begin transaction
  SQL (69.0ms)  INSERT INTO "uploads" ("created_at", "post_id", "updated_at", "upload_content_type", "upload_file_name", "upload_file_size", "upload_updated_at") VALUES (?, ?, ?, ?, ?, ?, ?)  [["created_at", Fri, 16 Mar 2012 16:19:53 UTC +00:00], ["post_id", nil], ["updated_at", Fri, 16 Mar 2012 16:19:53 UTC +00:00], ["upload_content_type", "image/png"], ["upload_file_name", "estimation_grid.png"], ["upload_file_size", 53079], ["upload_updated_at", Fri, 16 Mar 2012 16:19:53 UTC +00:00]]
   (13.8ms)  commit transaction
 => #<Upload id: 4, post_id: nil, created_at: "2012-03-16 16:19:53", updated_at: "2012-03-16 16:19:53", upload_file_name: "estimation_grid.png", upload_content_type: "image/png", upload_file_size: 53079, upload_updated_at: "2012-03-16 16:19:53">