code: def new_log_filepath(self):
          '''returns a filepath to a log which does not currently exist and is suitable for DF logging'''
          lastlog_filename = os.path.join(self.dataflash_dir,'LASTLOG.TXT')
          if os.path.exists(lastlog_filename) and os.stat(lastlog_filename).st_size != 0:
              fh = open(lastlog_filename,'rb')
              log_cnt = int(fh.read()) + 1
              fh.close()
          else:
              log_cnt = 1
  
          self.lastlog_file = open(lastlog_filename,'w+b')
          self.lastlog_file.write(log_cnt.__str__())
          self.lastlog_file.close()
  
          return os.path.join(self.dataflash_dir, '%u.BIN' % (log_cnt,))f new_log_filepath(self):
          '''returns a filepath to a log which does not currently exist and is suitable for DF logging'''
          lastlog_filename = os.path.join(self.dataflash_dir,'LASTLOG.TXT')
          if os.path.exists(lastlog_filename) and os.stat(lastlog_filename).st_size != 0:
              fh = open(lastlog_filename,'rb')
              log_cnt = int(fh.read()) + 1
              fh.close()
          else:
              log_cnt = 1
  
          self.lastlog_file = open(lastlog_filename,'w+b')
          self.lastlog_file.write(log_cnt.__str__())
          self.lastlog_file.close()
  
          return os.path.join(self.dataflash_dir, '%u.BIN' % (log_cnt,));
docs: returns a filepath to a log which does not currently exist and is suitable for DF logging