Merge remote-tracking branch 'upstream/3.4' into merge-3.4

modules/python/package/cv2/__init__.py

@@ -68,6 +68,13 @@ def bootstrap():
         sys.path.insert(1, p)
 
     if os.name == 'nt':
+        if sys.version_info[:2] >= (3, 8):  # https://github.com/python/cpython/pull/12302
+            for p in l_vars['BINARIES_PATHS']:
+                try:
+                    os.add_dll_directory(p)
+                except Exception as e:
+                    if DEBUG: print('Failed os.add_dll_directory(): '+ str(e))
+                    pass
         os.environ['PATH'] = ';'.join(l_vars['BINARIES_PATHS']) + ';' + os.environ.get('PATH', '')
         if DEBUG: print('OpenCV loader: PATH={}'.format(str(os.environ['PATH'])))
     else:

modules/python/package/setup.py

@@ -44,6 +44,7 @@ def main():
           'Programming Language :: Python :: 3.5',
           'Programming Language :: Python :: 3.6',
           'Programming Language :: Python :: 3.7',
+          'Programming Language :: Python :: 3.8',
           'Programming Language :: C++',
           'Programming Language :: Python :: Implementation :: CPython',
           'Topic :: Scientific/Engineering',