{* ../../docs_src/security/tutorial007_an_py39.py hl[1,12:24] *}

这类似于：

```Python
if not (credentials.username == "stanleyjobson") or not (credentials.password == "swordfish"):
    # Return some error
    ...
```

但使用 `secrets.compare_digest()`，可以防御**时差攻击**，更加安全。

### 时差攻击

什么是**时差攻击**？

假设攻击者试图猜出用户名与密码。

他们发送用户名为 `johndoe`，密码为 `love123`  的请求。

然后，Python 代码执行如下操作：

```Python

				done = true
			}
		case <-ctx.Done():
			// Refreshing is canceled
			return false, ctx.Err()
		}
		if done {
			break
		}
	}

	// We may have some unused results in ch, release them async.
	go func() {
		wg.Wait()
		xioutil.SafeClose(ch)
		for range ch {
		}
	}()

	noQuorum := lockNotFound > len(restClnts)-quorum
	return noQuorum, nil
}

		dst = make([]byte, 0, skip+1024)
	}
	dst = dst[:skip]
	if skip > 0 {
		n, err := io.ReadFull(r.buf, dst)
		if err != nil && err != io.ErrUnexpectedEOF {
			// If an EOF happens after reading some but not all the bytes,
			// ReadFull returns ErrUnexpectedEOF.
			return dst[:n], err
		}
		dst = dst[:n]
		if err == io.ErrUnexpectedEOF {
			return dst, io.EOF
		}
	}
	// Read until next line.

private
fun CtClass.isLikelyEquivalentTo(ktTypeReference: KtTypeReference): Boolean {
    val ktTypeAsText = ktTypeReference.text
    if (ktTypeAsText.contains(" -> ")) {
        // This is a function of some sort
        return name.startsWith("kotlin.jvm.functions.Function")
    }

    val ktTypeRawName = ktTypeAsText
        .trimEnd('?') // nullability is not part of JVM types

     * @return file paths to place on the different tool options
     */
    @Nonnull
    Map<PathType, List<Path>> getDispatchedPaths();

    /**
     * {@return all dependencies associated with their paths}
     * Some dependencies may be associated with a null value if there is no path available.
     */
    @Nonnull
    Map<Dependency, Path> getDependencies();

    /**

    }

    // These methods deal with construction intact Plugin object that look like they come from a standard
    // <plugin/> block in a Maven POM. We have to do some wiggling to pull the sources of information
    // together and this really shows the problem of constructing a sensible default configuration, but
    // it's all encapsulated here so it appears normalized to the POM builder.

    export TFCI_INSTALLER_WHL_PROJECT_NAME="$TFCI_INSTALLER_WHL_NIGHTLY_PROJECT_NAME"
  fi
  export project_name="$TFCI_INSTALLER_WHL_PROJECT_NAME"
fi

# Mac builds have some specific setup needs. See setup_macos.sh for details
if [[ "${OSTYPE}" =~ darwin* ]]; then
  source ./ci/official/utilities/setup_macos.sh
fi

# Create and expand to the full path of TFCI_OUTPUT_DIR

      | to be made available to plugin authors. If we find people are getting fancy and want to take advantage of
      | Guice specifics we can expose that later. Really some testing needs to be done to see full hiding
      | of Guice has any impact on what we may categorize as a standard JSR-330 based Tesla/Maven plugin.

        <exportedPackage>com.google.inject.*</exportedPackage>

            List<PluginUpgrade> upgrades = PluginUpgradeStrategy.getPluginUpgrades();

            assertFalse(upgrades.isEmpty(), "Should have predefined plugin upgrades");

            // Verify some expected plugins are included
            boolean hasCompilerPlugin =
                    upgrades.stream().anyMatch(upgrade -> "maven-compiler-plugin".equals(upgrade.artifactId()));
            boolean hasExecPlugin =

	if spc {
		s.WriteString(KvDoubleQuote)
	}
	s.WriteString(kv.Value)
	if spc {
		s.WriteString(KvDoubleQuote)
	}
	return s.String()
}

// KVS - is a shorthand for some wrapper functions
// to operate on list of key values.
type KVS []KV

// Empty - return if kv is empty
func (kvs KVS) Empty() bool {
	return len(kvs) == 0
}

// Clone - returns a copy of the KVS