def doc_of_type(text, type)
      raise "No Atom document of type: #{type}" unless @documents.include?(type.to_s)

      GoogleApps::Atom.send(type, text)
    end
def doc_of_type(text, type)
      raise "No Atom document of type: #{type}" unless @documents.include?(type.to_s)

      GoogleApps::Atom.send(type, text)
    end
doc_of_type takes a document type and a string and
 returns a document of that type in the current format.