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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_active_subject_set(self, request):
 """Get a set containing all subjects for which the current connection has been successfully authenticated."""

        # Handle complete certificate in vendor specific extension.
        if django.conf.settings.DEBUG_GMN:
            if 'HTTP_VENDOR_INCLUDE_CERTIFICATE' in request.META:
                request.META[
                    'SSL_CLIENT_CERT'
                ] = self.pem_in_http_header_to_pem_in_string(
                    request.META['HTTP_VENDOR_INCLUDE_CERTIFICATE']
                )

        # Add subjects from any provided certificate and JWT and store them in
        # the Django request obj.
        cert_primary_str, cert_equivalent_set = d1_gmn.app.middleware.session_cert.get_subjects(
            request
        )
        jwt_subject_list = d1_gmn.app.middleware.session_jwt.validate_jwt_and_get_subject_list(
            request
        )
        primary_subject_str = cert_primary_str
        all_subjects_set = (
            cert_equivalent_set | {cert_primary_str} | set(jwt_subject_list)
        )
        if len(jwt_subject_list) == 1:
            jwt_primary_str = jwt_subject_list[0]
            if jwt_primary_str != cert_primary_str:
                if cert_primary_str == d1_common.const.SUBJECT_PUBLIC:
                    primary_subject_str = jwt_primary_str
                else:
                    logging.warning(
                        'Both a certificate and a JWT were provided and the primary '
                        'subjects differ. Using the certificate for primary subject and'
                        'the JWT as equivalent.'
                    )

        logging.info('Primary active subject: {}'.format(primary_subject_str))
        logging.info(
            'All active subjects: {}'.format(', '.join(sorted(all_subjects_set)))
        )

        # Handle list of subjects in vendor specific extension:
        if django.conf.settings.DEBUG_GMN:
            # This is added to any subjects obtained from cert and/or JWT.
            if 'HTTP_VENDOR_INCLUDE_SUBJECTS' in request.META:
                request.all_subjects_set.update(
                    request.META['HTTP_VENDOR_INCLUDE_SUBJECTS'].split('\t')
                )

        return primary_subject_str, all_subjects_set