code: def start_output (self):
          
          super(CSVLogger, self).start_output()
          row = []
          if self.has_part("intro"):
              self.write_intro()
              self.flush()
          else:
              # write empty string to initialize file output
              self.write(u"")
          self.queue = StringIO()
          self.writer = csv.writer(self.queue, dialect=self.dialect,
                 delimiter=self.separator, lineterminator=self.linesep,
                 quotechar=self.quotechar)
          for s in Columns:
              if self.has_part(s):
                  row.append(s)
          if row:
              self.writerow(row)
docs: Write checking start info as csv comment.