bugfix: import error in example tests

examples/system/ota/native_ota_example/example_test.py

@@ -1,8 +1,6 @@
 import re
 import os
 import socket
-import BaseHTTPServer
-import SimpleHTTPServer
 from threading import Thread
 import ssl
 
@@ -11,6 +9,13 @@ import ttfw_idf
 import random
 import subprocess
 
+try:
+    import BaseHTTPServer
+    from SimpleHTTPServer import SimpleHTTPRequestHandler
+except ImportError:
+    import http.server as BaseHTTPServer
+    from http.server import SimpleHTTPRequestHandler
+
 server_cert = "-----BEGIN CERTIFICATE-----\n" \
               "MIIDXTCCAkWgAwIBAgIJAP4LF7E72HakMA0GCSqGSIb3DQEBCwUAMEUxCzAJBgNV\n"\
               "BAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBX\n"\
@@ -85,7 +90,7 @@ def start_https_server(ota_image_dir, server_ip, server_port):
     key_file_handle.close()
 
     httpd = BaseHTTPServer.HTTPServer((server_ip, server_port),
-                                      SimpleHTTPServer.SimpleHTTPRequestHandler)
+                                      SimpleHTTPRequestHandler)
 
     httpd.socket = ssl.wrap_socket(httpd.socket,
                                    keyfile=key_file,