ossl_x509_get_serial  710 ext/openssl/ossl_x509cert.c     rb_str_append(str, rb_inspect(ossl_x509_get_serial(self)));
ossl_x509_get_serial  746 ext/openssl/ossl_x509cert.c     rb_define_method(cX509Cert, "serial", ossl_x509_get_serial, 0);