docs: def mkpsf_failures():
      """A simple script to loop over the standard tags for the mkpsf and
      step1 processing steps. If exposure/ccd combo isn't marked as
      'success' then report the failure.
      
      This example uses the vos client directly.
      """
  
      for expnum in storage.list_dbimages():
          for ccd in range(36):
              if not storage.get_status(MKPSF, "", expnum, "p", ccd):
                  # get_status returns FALSE if process didn't succeed,
                  # with return_message=True it returns the error message.
                  print expnum, ccd, storage.get_status(MKPSF, "", expnum, "p", ccd, return_message=True)