change json.tool._group_to_theme_color formatting

Author: vstinner

Lib/json/tool.py

@@ -22,7 +22,13 @@
     (?P<null>null)
 ''', re.VERBOSE)
 
-_group_to_theme_color = frozendict(key="definition",string="string",number="number",boolean="keyword",null="keyword")
+_group_to_theme_color = frozendict({
+    "key": "definition",
+    "string": "string",
+    "number": "number",
+    "boolean": "keyword",
+    "null": "keyword",
+})
 
 
 def _colorize_json(json_str, theme):