Example for json.pretty (#10466)

lib/pure/json.nim

@@ -708,6 +708,25 @@ proc toPretty(result: var string, node: JsonNode, indent = 2, ml = true,
 proc pretty*(node: JsonNode, indent = 2): string =
   ## Returns a JSON Representation of `node`, with indentation and
   ## on multiple lines.
+  ##
+  ## Similar to prettyprint in Python.
+  ##
+  ## **Examples:**
+  ##
+  ## .. code-block:: Nim
+  ##   let j = %* {"name": "Isaac", "books": ["Robot Dreams"],
+  ##               "details": {"age":35, "pi":3.1415}}
+  ##   echo pretty(j)
+  ##   # {
+  ##   #   "name": "Isaac",
+  ##   #   "books": [
+  ##   #     "Robot Dreams"
+  ##   #   ],
+  ##   #   "details": {
+  ##   #     "age": 35,
+  ##   #     "pi": 3.1415
+  ##   #   }
+  ##   # }
   result = ""
   toPretty(result, node, indent)