diff --git a/.github/workflows/pymi-cd.yml b/.github/workflows/pymi-cd.yml
index 051cb1e..b8b8596 100644
--- a/.github/workflows/pymi-cd.yml
+++ b/.github/workflows/pymi-cd.yml
@@ -9,7 +9,7 @@ jobs:
     strategy:
       max-parallel: 100
       matrix:
-        python-version: ["3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
 
     steps:
     - uses: actions/checkout@v4
@@ -26,7 +26,7 @@ jobs:
         pip install . || exit /b
         python -m unittest discover || exit /b
         python setup.py bdist_wheel || exit /b
-    - uses: actions/upload-artifact@v3
+    - uses: actions/upload-artifact@v4
       with:
         name: pymi_wheel_py${{ matrix.python-version }}
         path: 'dist'
diff --git a/PyMI/PyMI.cpp b/PyMI/PyMI.cpp
index 9a7edf2..93cc14c 100644
--- a/PyMI/PyMI.cpp
+++ b/PyMI/PyMI.cpp
@@ -34,9 +34,9 @@ static PyModuleDef mimodule = {
 
 PyObject* _initmi(void)
 {
-    if (!PyEval_ThreadsInitialized())
+    if (!Py_IsInitialized())
     {
-        PyEval_InitThreads();
+        Py_Initialize();
     }
 
     PyDateTime_IMPORT;