code: def append(self, content, encoding='utf8'):
          
          if not self.parent.exists:
              self.parent.create()
          with open(self._filename, "ab") as output_file:
              if not is_text(content):
                  Log.error(u"expecting to write unicode only")
              output_file.write(content.encode(encoding))
              output_file.write(b"\n")
docs: add a line to file