docs: def ossos_discoveries(directory=parameters.REAL_KBO_AST_DIR,
                        suffix='ast',
                        no_nt_and_u=False,
                        single_object=None,
                        all_objects=True,
                        data_release=None,
                        ):
      """
      Returns a list of objects holding orbfit.Orbfit objects with the observations in the Orbfit.observations field.
      Default is to return only the objects corresponding to the current Data Release.
      """
      retval = []
      # working_context = context.get_context(directory)
      # files = working_context.get_listing(suffix)
      files = [f for f in os.listdir(directory) if (f.endswith('mpc') or f.endswith('ast') or f.endswith('DONE'))]
  
      if single_object is not None:
          files = filter(lambda name: name.startswith(single_object), files)
      elif all_objects and data_release is not None:
          # only return the objects corresponding to a particular Data Release
          data_release = ossos_release_parser(table=True, data_release=data_release)
          objects = data_release['object']
          files = filter(lambda name: name.partition(suffix)[0].rstrip('.') in objects, files)
  
      for filename in files:
          # keep out the not-tracked and uncharacteried.
          if no_nt_and_u and (filename.__contains__('nt') or filename.startswith('u')):
              continue
          # observations = mpc.MPCReader(directory + filename)
          mpc_filename = directory + filename
          abg_filename = os.path.abspath(directory + '/../abg/') + "/" + os.path.splitext(filename)[0] + ".abg"
          obj = TNO(None, ast_filename=mpc_filename, abg_filename=abg_filename)
          retval.append(obj)
  
      return retval