docs: String task1(AwsSigner4Request sr) {
          StringBuilder sb = new StringBuilder(sr.getMethod()).append('\n')
                  .append(sr.getUri().getRawPath()).append('\n')
                  .append(getCanonicalQuery(sr.getUri())).append('\n')
                  .append(sr.getCanonicalHeaders()).append('\n')
                  .append(sr.getSignedHeaders()).append('\n');
  
          hexEncode(sb, sha256(sr.getBytes()));
          return sb.toString();
      }