diff --git a/PHP_CoreFunctions.js b/PHP_CoreFunctions.js
new file mode 100644
index 0000000..6e7e670
--- /dev/null
+++ b/PHP_CoreFunctions.js
@@ -0,0 +1 @@
+module.exports =require('./src/PHP_CoreFunctions')
\ No newline at end of file
diff --git a/README.md b/README.md
index 2da474a..f5c29cf 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,14 @@ pdf.SetFont('Arial','B',12);
 pdf.Cell(5,5,"HOLA MUNDO!!");
 pdf.Output('F',`test.pdf`);
 ```` 
+# Como se Usa PHP_CoreFunctions 
+```javascript 
+const {isset} = require('node-fpdf/PHP_CoreFunctions')
+
+console.log(isset(1))
+
+```` 
+
 # **Fuentes Disponibles**
 - [x] courier
 - [x] helvetica
diff --git a/package.json b/package.json
index ad1b223..682c499 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "node-fpdf",
-  "version": "1.0.40",
+  "version": "1.0.41",
   "description": "port de la libreria de FPDF de PHP",
   "main": "index.js",
   "directories": {
@@ -29,7 +29,8 @@
     "test20": "node ./test/DashedRect.js",
     "test21": "node ./test/subWrite.js",
     "test22": "node ./test/labels_test.js",
-    "test23": "node ./test/testsetfont.js"
+    "test23": "node ./test/testsetfont.js",
+    "test24": "node ./test/test_phpfunctions.js"
   },
   "repository": {
     "type": "git",
diff --git a/test/test_phpfunctions.js b/test/test_phpfunctions.js
new file mode 100644
index 0000000..ada9cf4
--- /dev/null
+++ b/test/test_phpfunctions.js
@@ -0,0 +1,3 @@
+const {isset} = require('../PHP_CoreFunctions')
+
+console.log(isset(1))
\ No newline at end of file