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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_ssl_certificate( self, binary_form: bool = False ) -> Union[None, Dict, bytes]: """Returns the client's SSL certificate, if any. To use client certificates, the HTTPServer's `ssl.SSLContext.verify_mode` field must be set, e.g.:: ssl_ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH) ssl_ctx.load_cert_chain("foo.crt", "foo.key") ssl_ctx.load_verify_locations("cacerts.pem") ssl_ctx.verify_mode = ssl.CERT_REQUIRED server = HTTPServer(app, ssl_options=ssl_ctx) By default, the return value is a dictionary (or None, if no client certificate is present). If ``binary_form`` is true, a DER-encoded form of the certificate is returned instead. See SSLSocket.getpeercert() in the standard library for more details. http://docs.python.org/library/ssl.html#sslsocket-objects """

        try:
            if self.connection is None:
                return None
            # TODO: add a method to HTTPConnection for this so it can work with HTTP/2
            return self.connection.stream.socket.getpeercert(  # type: ignore
                binary_form=binary_form
            )
        except SSLError:
            return None