diff --git a/src/Base/Interpreter.cpp b/src/Base/Interpreter.cpp
index 03b74aee61..338d9b0e48 100644
--- a/src/Base/Interpreter.cpp
+++ b/src/Base/Interpreter.cpp
@@ -549,7 +549,11 @@ const char* InterpreterSingleton::init(int argc,char *argv[])
                 "    exec(open(activate_this).read(), {'__file__':activate_this})\n"
             );
         }
+
+#if PY_VERSION_HEX < 0x03090000
         PyEval_InitThreads();
+#endif
+
 #if PY_MAJOR_VERSION >= 3
         size_t size = argc;
         wchar_t **_argv = new wchar_t*[size];
@@ -700,7 +704,11 @@ void InterpreterSingleton::runMethod(PyObject *pobject, const char *method,
         throw TypeError("InterpreterSingleton::RunMethod() wrong arguments");
     }
 
+#if PY_VERSION_HEX < 0x03090000
     presult = PyEval_CallObject(pmeth, pargs);   /* run interpreter */
+#else
+    presult = PyObject_CallObject(pmeth, pargs);   /* run interpreter */
+#endif
 
     Py_DECREF(pmeth);
     Py_DECREF(pargs);
diff --git a/src/Base/PyTools.c b/src/Base/PyTools.c
index 3dc0a998eb..71785f9b94 100644
--- a/src/Base/PyTools.c
+++ b/src/Base/PyTools.c
@@ -58,7 +58,11 @@ PP_Run_Method(PyObject *pobject,  const char *method,
     if (PP_DEBUG)                                    /* debug it too? */ 
         presult = PP_Debug_Function(pmeth, pargs); 
     else 
+#if PY_VERSION_HEX < 0x03090000
         presult = PyEval_CallObject(pmeth, pargs);   /* run interpreter */
+#else
+        presult = PyObject_CallObject(pmeth, pargs);   /* run interpreter */
+#endif
 
     Py_DECREF(pmeth);
     Py_DECREF(pargs);
@@ -133,7 +137,11 @@ PP_Run_Function(const char *modname, const char *funcname,          /* load from
     if (PP_DEBUG && strcmp(modname, "pdb") != 0)    /* debug this call? */
         presult = PP_Debug_Function(func, args);    /* run in pdb; incref'd */
     else
+#if PY_VERSION_HEX < 0x03090000
         presult = PyEval_CallObject(func, args);    /* run function; incref'd */
+#else
+        presult = PyObject_CallObject(func, args);    /* run function; incref'd */
+#endif
 
     Py_DECREF(func);
     Py_DECREF(args);                                    /* result may be None */
@@ -185,7 +193,11 @@ PP_Run_Known_Callable(PyObject *object,               /* func|class|method */
     if (PP_DEBUG)                                   /* debug this call? */
         presult = PP_Debug_Function(object, args);  /* run in pdb; incref'd */
     else
+#if PY_VERSION_HEX < 0x03090000
         presult = PyEval_CallObject(object, args);  /* run function; incref'd */
+#else
+        presult = PyObject_CallObject(object, args);  /* run function; incref'd */
+#endif
 
     Py_DECREF(args);                                    /* result may be None */
     return PP_Convert_Result(presult, resfmt, cresult); /* convert result to C*/
diff --git a/src/CXX/Python3/Objects.hxx b/src/CXX/Python3/Objects.hxx
index 490978ec8d..e5b341a012 100644
--- a/src/CXX/Python3/Objects.hxx
+++ b/src/CXX/Python3/Objects.hxx
@@ -3164,14 +3164,36 @@ namespace Py
         // Call with keywords
         Object apply( const Tuple &args, const Dict &kw ) const
         {
+#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 9
+            PyObject *result = PyObject_Call( ptr(), args.ptr(), kw.ptr() );
+#else
             PyObject *result = PyEval_CallObjectWithKeywords( ptr(), args.ptr(), kw.ptr() );
+#endif
             if( result == NULL )
             {
                 throw Exception();
             }
             return asObject( result );
         }
+#if PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 9
+        Object apply() const
+        {
+            PyObject *result = PyObject_CallNoArgs( ptr() );
+            return asObject( result );
+        }
 
+        Object apply( PyObject *pargs ) const
+        {
+            if( pargs == 0 )
+            {
+                return apply( Tuple() );
+            }
+            else
+            {
+                return apply( Tuple( pargs ) );
+            }
+        }
+#else
         Object apply( PyObject *pargs = 0 ) const
         {
             if( pargs == 0 )
@@ -3183,6 +3205,7 @@ namespace Py
                 return apply( Tuple( pargs ) );
             }
         }
+#endif
     };
 
     class PYCXX_EXPORT Module: public Object
@@ -3233,8 +3256,7 @@ namespace Py
     inline Object Object::callMemberFunction( const std::string &function_name ) const
     {
         Callable target( getAttr( function_name ) );
-        Tuple args( (sequence_index_type)0 );
-        return target.apply( args );
+        return target.apply();
     }
 
     inline Object Object::callMemberFunction( const std::string &function_name, const Tuple &args ) const
diff --git a/src/CXX/Python3/cxx_extensions.cxx b/src/CXX/Python3/cxx_extensions.cxx
index 9ff94612f0..d4e597f5e7 100644
--- a/src/CXX/Python3/cxx_extensions.cxx
+++ b/src/CXX/Python3/cxx_extensions.cxx
@@ -222,7 +222,7 @@ extern "C"
     // All the following functions redirect the call from Python
     // onto the matching virtual function in PythonExtensionBase
     //
-#ifdef PYCXX_PYTHON_2TO3
+#if defined( PYCXX_PYTHON_2TO3 ) && !defined( Py_LIMITED_API ) && PY_MINOR_VERSION <= 7
     static int print_handler( PyObject *, FILE *, int );
 #endif
     static PyObject *getattr_handler( PyObject *, char * );
@@ -622,7 +622,7 @@ PythonExtensionBase *getPythonExtensionBase( PyObject *self )
     }
 }
 
-#ifdef PYCXX_PYTHON_2TO3
+#if defined( PYCXX_PYTHON_2TO3 ) && !defined( Py_LIMITED_API ) && PY_MINOR_VERSION <= 7
 extern "C" int print_handler( PyObject *self, FILE *fp, int flags )
 {
     try
diff --git a/src/Gui/OnlineDocumentation.cpp b/src/Gui/OnlineDocumentation.cpp
index f740e1cdce..5504607948 100644
--- a/src/Gui/OnlineDocumentation.cpp
+++ b/src/Gui/OnlineDocumentation.cpp
@@ -419,7 +419,11 @@ void StdCmdPythonHelp::activated(int iMsg)
                 char szBuf[201];
                 snprintf(szBuf, 200, "http://localhost:%d", port);
                 PyObject* args = Py_BuildValue("(s)", szBuf);
+#if PY_VERSION_HEX < 0x03090000
                 PyObject* result = PyEval_CallObject(func,args);
+#else
+                PyObject* result = PyObject_CallObject(func,args);
+#endif
                 if (result)
                     failed = false;
         
@@ -455,7 +459,11 @@ bool Gui::OpenURLInBrowser(const char * URL)
         PyObject* func = PyDict_GetItemString(dict, "open");
         if (func) {
             PyObject* args = Py_BuildValue("(s)", URL);
+#if PY_VERSION_HEX < 0x03090000
             PyObject* result = PyEval_CallObject(func,args);
+#else
+            PyObject* result = PyObject_CallObject(func,args);
+#endif
             if (result)
                 failed = false;
         
diff --git a/src/Gui/PythonConsole.cpp b/src/Gui/PythonConsole.cpp
index 21fc9ce5c4..e866055a76 100644
--- a/src/Gui/PythonConsole.cpp
+++ b/src/Gui/PythonConsole.cpp
@@ -141,7 +141,11 @@ InteractiveInterpreter::InteractiveInterpreter()
     PyObject* func = PyObject_GetAttrString(module, "InteractiveInterpreter");
     PyObject* args = Py_BuildValue("()");
     d = new InteractiveInterpreterP;
+#if PY_VERSION_HEX < 0x03090000
     d->interpreter = PyEval_CallObject(func,args);
+#else
+    d->interpreter = PyObject_CallObject(func,args);
+#endif
     Py_DECREF(args);
     Py_DECREF(func);
     Py_DECREF(module);
@@ -195,7 +199,11 @@ PyObject* InteractiveInterpreter::compile(const char* source) const
     Base::PyGILStateLocker lock;
     PyObject* func = PyObject_GetAttrString(d->interpreter, "compile");
     PyObject* args = Py_BuildValue("(s)", source);
+#if PY_VERSION_HEX < 0x03090000
     PyObject* eval = PyEval_CallObject(func,args);  // must decref later
+#else
+    PyObject* eval = PyObject_CallObject(func,args);  // must decref later
+#endif
 
     Py_DECREF(args);
     Py_DECREF(func);
@@ -227,7 +235,11 @@ int InteractiveInterpreter::compileCommand(const char* source) const
     Base::PyGILStateLocker lock;
     PyObject* func = PyObject_GetAttrString(d->interpreter, "compile");
     PyObject* args = Py_BuildValue("(s)", source);
+#if PY_VERSION_HEX < 0x03090000
     PyObject* eval = PyEval_CallObject(func,args);  // must decref later
+#else
+    PyObject* eval = PyObject_CallObject(func,args);  // must decref later
+#endif
 
     Py_DECREF(args);
     Py_DECREF(func);
diff --git a/src/Gui/WidgetFactory.cpp b/src/Gui/WidgetFactory.cpp
index c47a76ef42..64da98a726 100644
--- a/src/Gui/WidgetFactory.cpp
+++ b/src/Gui/WidgetFactory.cpp
@@ -1677,7 +1677,11 @@ void SignalConnect::onExecute()
 
     /* Time to call the callback */
     arglist = Py_BuildValue("(O)", myResource);
+#if PY_VERSION_HEX < 0x03090000
     result = PyEval_CallObject(myCallback, arglist);
+#else
+    result = PyObject_CallObject(myCallback, arglist);
+#endif
     Py_XDECREF(result);
     Py_DECREF(arglist);
 }
diff --git a/src/Gui/Widgets.cpp b/src/Gui/Widgets.cpp
index 8b4cd8774f..158766e2e3 100644
--- a/src/Gui/Widgets.cpp
+++ b/src/Gui/Widgets.cpp
@@ -850,7 +850,11 @@ void UrlLabel::mouseReleaseEvent (QMouseEvent *)
         PyObject* func = PyDict_GetItemString(dict, "open");
         if (func) {
             PyObject* args = Py_BuildValue("(s)", (const char*)this->_url.toLatin1());
+#if PY_VERSION_HEX < 0x03090000
             PyObject* result = PyEval_CallObject(func,args);
+#else
+            PyObject* result = PyObject_CallObject(func,args);
+#endif
             // decrement the args and module reference
             Py_XDECREF(result);
             Py_DECREF(args);
diff --git a/src/Mod/Part/App/AppPartPy.cpp b/src/Mod/Part/App/AppPartPy.cpp
index 6bbee793bb..b4143b1520 100644
--- a/src/Mod/Part/App/AppPartPy.cpp
+++ b/src/Mod/Part/App/AppPartPy.cpp
@@ -1841,11 +1841,11 @@ private:
             if (!p) {
                 throw Py::TypeError("** makeWireString can't convert PyString.");
             }
-            pysize = PyUnicode_GetSize(p);
+            pysize = PyUnicode_GetLength(p);
             unichars = PyUnicode_AS_UNICODE(p);
         }
         else if (PyUnicode_Check(intext)) {
-            pysize = PyUnicode_GetSize(intext);
+            pysize = PyUnicode_GetLength(intext);
             unichars = PyUnicode_AS_UNICODE(intext);
         }
         else {