Updating setup.py to work with python 3.12

setup.py

@@ -1,4 +1,20 @@
-import imp
+try:
+    from imp import load_source
+except ImportError:
+    import importlib.util
+    import importlib.machinery
+
+    def load_source(modname, filename):
+        loader = importlib.machinery.SourceFileLoader(modname, filename)
+        spec = importlib.util.spec_from_file_location(modname, filename, loader=loader)
+        module = importlib.util.module_from_spec(spec)
+        # The module is always executed and not cached in sys.modules.
+        # Uncomment the following line to cache the module.
+        # sys.modules[module.__name__] = module
+        loader.exec_module(module)
+        return module
+
+
 import os
 
 try:
@@ -16,8 +32,8 @@
     README = ''
     CHANGES = ''
 
-# Use imp to avoid sift/__init__.py
-version_mod = imp.load_source('__tmp', os.path.join(here, 'sift/version.py'))
+# Use imp/importlib to avoid sift/__init__.py
+version_mod = load_source('__tmp', os.path.join(here, 'sift/version.py'))
 
 setup(
     name='Sift',