code: def export(self, new_format, filename=None, chan=None, begtime=None,
                 endtime=None):
          
          dataset = self.dataset
          subj_id = dataset.header['subj_id']
          if filename is None:
              filename = dataset.filename
  
          data = dataset.read_data(chan=chan, begtime=begtime, endtime=endtime)
  
          if 'wonambi' == new_format:
              write_wonambi(data, filename, subj_id=subj_id)
  
          elif 'edf' == new_format:
              write_edf(data, filename, subj_id=subj_id)
  
          else:
              self.parent.statusBar().showMessage('Format unrecognized.')
docs: Export current dataset to wonambi format (.won).
  
          Parameters
          ----------
          new_format : str
              Format for exported record: 'edf' or 'wonambi'
          filename : str or PosixPath
              filename to export to
          chan : list of str, opt
              list of original channel names to export. if None, all channels are
              exported
          begtime : int or datedelta or datetime
              start of the data to read;
              if it's int or float, it's assumed it's s;
              if it's timedelta, it's assumed from the start of the recording;
              if it's datetime, it's assumed it's absolute time.
          endtime : int or datedelta or datetime
              end of the data to read;
              if it's int or float, it's assumed it's s;
              if it's timedelta, it's assumed from the start of the recording;
              if it's datetime, it's assumed it's absolute time.