Reverted back to fixing _extensions at top level

package.json

@@ -4,7 +4,7 @@
     "type": "git",
     "url": "https://github.com/nktnet1/import-sync"
   },
-  "version": "2.0.3",
+  "version": "2.0.4",
   "files": [
     "dist"
   ],

src/import.ts

@@ -11,7 +11,15 @@ import { getCallerFilePath } from './files';
  */
 /* istanbul ignore next */
 const createEs6Require = (esmOptions: ESMOptions) => {
+  /**
+   * Removes the error for "[ERR_REQUIRE_ESM]: require() of ES Module", as per
+   * - https://github.com/standard-things/esm/issues/855#issuecomment-657982788
+   */
+  require('module').Module._extensions['.js'] = (m: any, filename: string) => {
+    m._compile(fs.readFileSync(filename, 'utf-8'), filename);
+  };
   const loader = esm(module, esmOptions);
+
   const newModule = module.constructor.length > 1 ? module.constructor : loader('module');
   const oldResolveFilename = newModule._resolveFilename;
   /**
@@ -23,14 +31,6 @@ const createEs6Require = (esmOptions: ESMOptions) => {
     const newRequest = request.startsWith('node:') ? request.substring(5) : request;
     return oldResolveFilename.call(this, newRequest, parent, isMain);
   };
-  /**
-   * Removes the error for "[ERR_REQUIRE_ESM]: require() of ES Module", as per
-   * - https://github.com/standard-things/esm/issues/855#issuecomment-657982788
-   */
-  newModule._extensions['.js'] = (m: any, filename: string) => {
-    m._compile(fs.readFileSync(filename, 'utf-8'), filename);
-  };
-
   return loader;
 };