@Override
        public String getAsString(final Object value) {
            if (value instanceof Date) {
                return DEFAULT_DATE_PRINTER.print(((Date) value).getTime());
            }
            return null;
        }

        @Override
        public Object getAsObject(final String value) {
            if (StringUtil.isEmpty(value)) {

					continue
				}
				filteredGws = append(filteredGws, gw)
			}
			err = printWaypointStatus(ctx, w, kubeClient, filteredGws)
			if err != nil {
				return fmt.Errorf("failed to print waypoint status: %v", err)
			}
			return w.Flush()
		},
	}

	waypointGenerateCmd := &cobra.Command{
		Use:   "generate",
		Short: "Generate a waypoint configuration",

  // `items` is a list of request-priorities.
  repeated PriorityLevelConfiguration items = 2;
}

// PriorityLevelConfigurationReference contains information that points to the "request-priority" being used.
message PriorityLevelConfigurationReference {
  // `name` is the name of the priority level configuration being referenced
  // Required.
  optional string name = 1;
}

	trailers      http.Header

	chunkSHA256Writer hash.Hash // Calculates sha256 of chunk data.
	buffer            []byte
	offset            int
	err               error
	debug             bool // Print details on failure. Add your own if more are needed.
}

func (cr *s3ChunkedReader) Close() (err error) {
	return nil
}

// Now, we read one chunk from the underlying reader.

        }

        DfsReferralDataInternal dr = null;
        long now = System.currentTimeMillis();
        synchronized ( this.domainsLock ) {
            /*
             * domains that can contain DFS points to maps of roots for each
             */
            Map<String, Map<String, CacheEntry<DfsReferralDataInternal>>> domains = getTrustedDomains(tf);
            if ( domains != null ) {

Por exemplo, você pode definir um arquivo `main.py` com o seguinte código:

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// dica

O segundo parâmetro em <a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> é o valor padrão para o retorno.

                    }
                }
                buf.append('}');
                buf.append('\n');
                try {
                    response.getWriter().print(buf.toString());
                } catch (final IOException e) {
                    throw new IORuntimeException(e);
                }
                return true;
            }, OptionalThing.empty());

        do {
          entryIndex = next - 1;
          entry = entries[entryIndex];
          next = CompactHashing.getNext(entry, mask);
        } while (next != srcNext);
        // here, entries[entryIndex] points to the old entry location; update it
        entries[entryIndex] = CompactHashing.maskCombine(entry, dstIndex + 1, mask);
      }
    } else {
      elements[dstIndex] = null;
      entries[dstIndex] = 0;
    }

デフォルトの例外ハンドラを`fastapi.exception_handlers`からインポートして再利用することができます:

```Python hl_lines="2 3 4 5 15 21"
{!../../docs_src/handling_errors/tutorial006.py!}
```

この例では、非常に表現力のあるメッセージでエラーを`print`しています。

////

### 在 Python 中读取环境变量

您还可以在 Python 之外的地方（例如终端中或使用任何其他方法）创建环境变量，然后在 Python 中读取它们。

例如，您可以有一个名为 `main.py` 的文件，其中包含以下内容：

```Python hl_lines="3"
import os

name = os.getenv("MY_NAME", "World")
print(f"Hello {name} from Python")
```

/// tip

<a href="https://docs.python.org/3.8/library/os.html#os.getenv" class="external-link" target="_blank">`os.getenv()`</a> 的第二个参数是要返回的默认值。