add hw2

node_modules/lodash-es/mapKeys.js

@@ -0,0 +1,36 @@
+import baseAssignValue from './_baseAssignValue.js';
+import baseForOwn from './_baseForOwn.js';
+import baseIteratee from './_baseIteratee.js';
+
+/**
+ * The opposite of `_.mapValues`; this method creates an object with the
+ * same values as `object` and keys generated by running each own enumerable
+ * string keyed property of `object` thru `iteratee`. The iteratee is invoked
+ * with three arguments: (value, key, object).
+ *
+ * @static
+ * @memberOf _
+ * @since 3.8.0
+ * @category Object
+ * @param {Object} object The object to iterate over.
+ * @param {Function} [iteratee=_.identity] The function invoked per iteration.
+ * @returns {Object} Returns the new mapped object.
+ * @see _.mapValues
+ * @example
+ *
+ * _.mapKeys({ 'a': 1, 'b': 2 }, function(value, key) {
+ *   return key + value;
+ * });
+ * // => { 'a1': 1, 'b2': 2 }
+ */
+function mapKeys(object, iteratee) {
+  var result = {};
+  iteratee = baseIteratee(iteratee, 3);
+
+  baseForOwn(object, function(value, key, object) {
+    baseAssignValue(result, iteratee(value, key, object), value);
+  });
+  return result;
+}
+
+export default mapKeys;