add hw2

node_modules/ramda/es/internal/_xchain.js

@@ -0,0 +1,11 @@
+import _curry2 from "./_curry2.js";
+import _flatCat from "./_flatCat.js";
+import map from "../map.js";
+
+var _xchain =
+/*#__PURE__*/
+_curry2(function _xchain(f, xf) {
+  return map(f, _flatCat(xf));
+});
+
+export default _xchain;