code: def losc_frame_urls(ifo, start_time, end_time):
      
      data = losc_frame_json(ifo, start_time, end_time)['strain']
      return [d['url'] for d in data if d['format'] == 'gwf']
docs: Get a list of urls to losc frame files
  
      Parameters
      ----------
      ifo: str
          The name of the IFO to find the information about.
      start_time: int
          The gps time in GPS seconds
      end_time: int
          The end time in GPS seconds
  
      Returns
      -------
      frame_files: list
          A dictionary containing information about the files that span the
          requested times.