nodes: 0, module; 1, function_definition; 2, function_name:sort_func; 3, parameters; 4, block; 5, identifier:self; 6, identifier:key; 7, expression_statement; 8, if_statement; 9, if_statement; 10, if_statement; 11, if_statement; 12, if_statement; 13, if_statement; 14, if_statement; 15, return_statement; 16, comment:"""Used to sort keys when writing Entry to JSON format.
  
          Should be supplemented/overridden by inheriting classes.
          """; 17, comparison_operator:key == self._KEYS.SCHEMA; 18, block; 19, comparison_operator:key == self._KEYS.NAME; 20, block; 21, comparison_operator:key == self._KEYS.SOURCES; 22, block; 23, comparison_operator:key == self._KEYS.ALIAS; 24, block; 25, comparison_operator:key == self._KEYS.MODELS; 26, block; 27, comparison_operator:key == self._KEYS.PHOTOMETRY; 28, block; 29, comparison_operator:key == self._KEYS.SPECTRA; 30, block; 31, identifier:key; 32, identifier:key; 33, attribute; 34, return_statement; 35, identifier:key; 36, attribute; 37, return_statement; 38, identifier:key; 39, attribute; 40, return_statement; 41, identifier:key; 42, attribute; 43, return_statement; 44, identifier:key; 45, attribute; 46, return_statement; 47, identifier:key; 48, attribute; 49, return_statement; 50, identifier:key; 51, attribute; 52, return_statement; 53, attribute; 54, identifier:SCHEMA; 55, string; 56, attribute; 57, identifier:NAME; 58, string; 59, attribute; 60, identifier:SOURCES; 61, string; 62, attribute; 63, identifier:ALIAS; 64, string; 65, attribute; 66, identifier:MODELS; 67, string; 68, attribute; 69, identifier:PHOTOMETRY; 70, string; 71, attribute; 72, identifier:SPECTRA; 73, string; 74, identifier:self; 75, identifier:_KEYS; 76, string_content:aaa; 77, identifier:self; 78, identifier:_KEYS; 79, string_content:aab; 80, identifier:self; 81, identifier:_KEYS; 82, string_content:aac; 83, identifier:self; 84, identifier:_KEYS; 85, string_content:aad; 86, identifier:self; 87, identifier:_KEYS; 88, string_content:aae; 89, identifier:self; 90, identifier:_KEYS; 91, string_content:zzy; 92, identifier:self; 93, identifier:_KEYS; 94, string_content:zzz
code: def sort_func(self, key):
          """Used to sort keys when writing Entry to JSON format.
  
          Should be supplemented/overridden by inheriting classes.
          """
          if key == self._KEYS.SCHEMA:
              return 'aaa'
          if key == self._KEYS.NAME:
              return 'aab'
          if key == self._KEYS.SOURCES:
              return 'aac'
          if key == self._KEYS.ALIAS:
              return 'aad'
          if key == self._KEYS.MODELS:
              return 'aae'
          if key == self._KEYS.PHOTOMETRY:
              return 'zzy'
          if key == self._KEYS.SPECTRA:
              return 'zzz'
          return key