def getContext(self):
            """
            Create a context for the server side of the connection.

            @return: an SSL context using a certificate and key.
            @rtype: C{OpenSSL.SSL.Context}
            """
            ctx = SSL.Context(SSL.TLSv1_METHOD)
            if chainedCertFile is not None:
                ctx.use_certificate_chain_file(chainedCertFile)
            ctx.use_privatekey_file(privateKeyFile)
            # Let the test author know if they screwed something up.
            ctx.check_privatekey()
            return ctx

            Create a context for the server side of the connection.

            @return: an SSL context using a certificate and key.
            @rtype: C{OpenSSL.SSL.Context}
            
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_sslverify.py