Traceback with set_context

C:\Python27\python.exe C:/Users/user/git/mitmproxy/mitmdump -v --cert ca/full.pem
127.0.0.1:57397: clientconnect
127.0.0.1:57397: request
  -> CONNECT example.com:443 HTTP/1.1
127.0.0.1:57397: Set new server address: example.com:443
127.0.0.1:57397: serverconnect
  -> example.com:443
127.0.0.1:57397: Received CONNECT request to SSL port. Upgrading to SSL...
127.0.0.1:57397: Establish SSL
  -> with client
  -> with server (sni: None)
handle_sni for <OpenSSL.SSL.Connection object at 0x023B4790>
127.0.0.1:57397: SNI received: example.com
exceptioned: SSL handshake error: Error([('SSL routines', 'SSL3_GET_CLIENT_HELLO', 'no shared cipher')],)
127.0.0.1:57397: SSL handshake error: The client may not trust the proxy's certificate.
127.0.0.1:57397: ProxyError('NetLibError("SSL handshake error: Error([(\'SSL routines\', \'SSL3_GET_CLIENT_HELLO\', \'no shared cipher\')],)",)',)
127.0.0.1:57397: serverdisconnect
  -> example.com:443
127.0.0.1:57397: clientdisconnect

Process finished with exit code -1073741819 (0xC0000005)

Traceback without set_context

C:\Python27\python.exe C:/Users/user/git/mitmproxy/mitmdump -v --cert ca/full.pem
127.0.0.1:57380: clientconnect
127.0.0.1:57380: request
  -> CONNECT example.com:443 HTTP/1.1
127.0.0.1:57380: Set new server address: example.com:443
127.0.0.1:57380: serverconnect
  -> example.com:443
127.0.0.1:57380: Received CONNECT request to SSL port. Upgrading to SSL...
127.0.0.1:57380: Establish SSL
  -> with client
  -> with server (sni: None)
handle_sni for <OpenSSL.SSL.Connection object at 0x023D4790>
127.0.0.1:57380: SNI received: example.com
exceptioned: SSL handshake error: Error([('SSL routines', 'SSL3_GET_CLIENT_HELLO', 'no shared cipher')],)
127.0.0.1:57380: SSL handshake error: The client may not trust the proxy's certificate.
127.0.0.1:57380: ProxyError('NetLibError("SSL handshake error: Error([(\'SSL routines\', \'SSL3_GET_CLIENT_HELLO\', \'no shared cipher\')],)",)',)
handle_sni for <OpenSSL.SSL.Connection object at 0x023D4790>
127.0.0.1:57380: serverdisconnect
  -> example.com:443
127.0.0.1:57380: clientdisconnect
127.0.0.1:57380: SNI received: example.com
127.0.0.1:57380: Error in handle_sni:
Traceback (most recent call last):
  File "C:\Users\user\git\mitmproxy\libmproxy\proxy\server.py", line 278, in handle_sni
    cert, key = self.find_cert()
  File "C:\Users\user\git\mitmproxy\libmproxy\proxy\server.py", line 247, in find_cert
    host = self.server_conn.address.host
AttributeError: 'NoneType' object has no attribute 'address'

Trigger

curl -x http://127.0.0.1:8080 https://example.com