541     sslcontext.options |= getattr(ssl, 'OP_SINGLE_ECDH_USE', 0)

   541     sslcontext.options |= getattr(ssl, 'OP_SINGLE_ECDH_USE', 0)

   542 

   542 

   543     # Use the list of more secure ciphers if found in the ssl module.

   543     # Use the list of more secure ciphers if found in the ssl module.

   544     if util.safehasattr(ssl, b'_RESTRICTED_SERVER_CIPHERS'):

   544     if util.safehasattr(ssl, b'_RESTRICTED_SERVER_CIPHERS'):

   545         sslcontext.options |= getattr(ssl, 'OP_CIPHER_SERVER_PREFERENCE', 0)

   545         sslcontext.options |= getattr(ssl, 'OP_CIPHER_SERVER_PREFERENCE', 0)

   546         sslcontext.set_ciphers(ssl._RESTRICTED_SERVER_CIPHERS)

   547         sslcontext.set_ciphers(ssl._RESTRICTED_SERVER_CIPHERS)

   547 

   549 

   548     if requireclientcert:

   550     if requireclientcert:

   549         sslcontext.verify_mode = ssl.CERT_REQUIRED

   551         sslcontext.verify_mode = ssl.CERT_REQUIRED

   550     else:

   552     else:

   551         sslcontext.verify_mode = ssl.CERT_NONE

   553         sslcontext.verify_mode = ssl.CERT_NONE