Multiple file uploads with HTTPoison

multipartbody.ex

{:multipart, [
    {:file, path, {"form-data", [{"name", "form_field_name"}, {"filename", Path.basename(path)}]},
    [{"Content-Type", MIME.from_path(path)}
  ],
  [
    {:file, path, {"form-data", [{"name", "another_name"}, {"filename", Path.basename(another_path)}]},
    [{"Content-Type", MIME.from_path(another_path)}
  ]
}