Add json module

rt/include/python/json.hpp

+//
+// Created by Tom on 04/07/2023.
+//
+
+#ifndef TYPON_JSON_HPP
+#define TYPON_JSON_HPP
+
+#include "builtins.hpp"
+
+namespace py_json {
+struct json_t {
+  template <typename T> typon::Task<void> dump(const T &x, PyFile &fp) {
+    std::stringstream ss;
+    repr_to(x, ss);
+    co_await fp.write(ss.str());
+  }
+} all;
+
+auto &get_all() { return all; }
+} // namespace py_json
+
+#endif // TYPON_JSON_HPP

trans/stdlib/json.py

+# coding: utf-8
+
+from typing import TypeVar
+
+T = TypeVar("T")
+
+def dump(obj: T, fp: file) -> Task[str]: ...
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