for k := range mapValue {
		keys = append(keys, k)
	}
	sort.Strings(keys)

	for _, k := range keys {
		value := mapValue[k]
		if stmt.Schema != nil {
			if field := stmt.Schema.LookUpField(k); field != nil {
				k = field.DBName
			}
		}

		if v, ok := selectColumns[k]; (ok && v) || (!ok && !restricted) {
			values.Columns = append(values.Columns, clause.Column{Name: k})

            sb.append("Vertex:  ").append(v.getMd().toString()).append('\n');
            List<MetadataGraphEdge> ins = getIncidentEdges(v);
            if (ins != null) {
                for (MetadataGraphEdge e : ins) {
                    sb.append("       from :  ").append(e.toString()).append('\n');
                }
            } else {
                sb.append("      no entries\n");
            }

            final StringBuilder queryBuf = new StringBuilder();
            queryBuf.append(termRangeQuery.includesLower() ? '[' : '{');
            final BytesRef lowerTerm = termRangeQuery.getLowerTerm();
            queryBuf.append(lowerTerm != null ? "*".equals(Term.toString(lowerTerm)) ? "\\*" : Term.toString(lowerTerm) : "*");
            queryBuf.append(" TO ");
            final BytesRef upperTerm = termRangeQuery.getUpperTerm();

        Iterator<String> iter = keySet().iterator();
        while (iter.hasNext()) {
            String key = iter.next();
            buffer.append(key).append('=').append(get(key));
            if (iter.hasNext()) {
                buffer.append('\n');
            }
        }
        return buffer.toString();
    }

            try {
                final long count = b.process();
                resultBuf.append(b.getClass().getSimpleName()).append(" : ").append(count).append('\n');
            } catch (final Exception e) {
                logger.warn("Failed to update scores: booster={}", b.getClass().getSimpleName(), e);
                resultBuf.append(e.getMessage()).append('\n');
            }
        });
        return resultBuf.toString();
    }

# Utiliser des dataclasses { #using-dataclasses }

FastAPI est construit au‑dessus de **Pydantic**, et je vous ai montré comment utiliser des modèles Pydantic pour déclarer les requêtes et les réponses.

Mais FastAPI prend aussi en charge l'utilisation de [`dataclasses`](https://docs.python.org/3/library/dataclasses.html) de la même manière :

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

	// string "v"
	o = append(o, 0x86, 0xa1, 0x76)
	o = msgp.AppendInt(o, z.Version)
	// string "ss"
	o = append(o, 0xa2, 0x73, 0x73)
	o, err = z.Status.MarshalMsg(o)
	if err != nil {
		err = msgp.WrapError(err, "Status")
		return
	}
	// string "did"
	o = append(o, 0xa3, 0x64, 0x69, 0x64)
	o = msgp.AppendString(o, z.DeplID)
	// string "bkts"
	o = append(o, 0xa4, 0x62, 0x6b, 0x74, 0x73)

		o = append(o, 0xa2, 0x6f, 0x73)
		o = msgp.AppendUint64(o, z.Objects)
		// string "vs"
		o = append(o, 0xa2, 0x76, 0x73)
		o = msgp.AppendUint64(o, z.Versions)
		// string "dms"
		o = append(o, 0xa3, 0x64, 0x6d, 0x73)
		o = msgp.AppendUint64(o, z.DeleteMarkers)
		// string "szs"
		o = append(o, 0xa3, 0x73, 0x7a, 0x73)
		o = msgp.AppendArrayHeader(o, uint32(dataUsageBucketLen))

        sb.append("CompressionNegotiateContext{");
        sb.append("flags=0x").append(Integer.toHexString(flags));
        sb.append(", algorithms=[");
        if (compressionAlgorithms != null) {
            for (int i = 0; i < compressionAlgorithms.length; i++) {
                if (i > 0)
                    sb.append(", ");
                sb.append(getAlgorithmName(compressionAlgorithms[i]));

				if vs, ok := defaultValueFieldsHavingValue[field]; ok {
					values.Columns = append(values.Columns, clause.Column{Name: field.DBName})
					for idx := range values.Values {
						if vs[idx] == nil {
							values.Values[idx] = append(values.Values[idx], stmt.DefaultValueOf(field))
						} else {
							values.Values[idx] = append(values.Values[idx], vs[idx])
						}
					}
				}
			}
		case reflect.Struct: