def update_information
      doc = Yomu.new(self.doc.url)
      self.num_of_pages = doc.metadata['xmpTPg:NPages']
      self.file_updated_at = doc.metadata['modified'] || doc.metadata['Creation-Date'] || Time.now
      self.file_created_at =  doc.metadata['Creation-Date'] || Time.now
   end

*** Psych::SyntaxError Exception: (<unknown>): mapping values are not allowed in this context at line 23 column 15

begin
  doc = Yomu.new(self.doc.url)
  self.num_of_pages = doc.metadata['xmpTPg:NPages']
  self.file_updated_at = doc.metadata['modified'] || doc.metadata['Creation-Date'] || Time.now
  self.file_created_at =  doc.metadata['Creation-Date'] || Time.now
rescue Psych::SyntaxError, StandardError => e
  print e
end