for key, value in update_dict.items():
        if (
            key in main_dict
            and isinstance(main_dict[key], dict)
            and isinstance(value, dict)
        ):
            deep_dict_update(main_dict[key], value)
        elif (
            key in main_dict
            and isinstance(main_dict[key], list)
            and isinstance(update_dict[key], list)

We can do better...

## What makes a dependency

Up to now you have seen dependencies declared as functions.

But that's not the only way to declare dependencies (although it would probably be the more common).

The key factor is that a dependency should be a "callable".

                        .getProvides()
                        .get("key"));
        assertNotNull(result.getProblems());
        assertEquals(0, result.getProblems().size());
    }

    @Test
    void testBuildRequestWithGlobalToolchains() throws Exception {
        Properties props = new Properties();
        props.put("key", "global_value");
        ToolchainModel toolchain = new ToolchainModel();

                        result.addException(exception);
                    }
                }
            } else {
                String key = SNAPSHOT + getKey(artifact.getClassifier(), artifact.getExtension());
                merge(infos, SNAPSHOT, key);
                if (!resolve(result, infos, key)) {
                    result.setVersion(version);
                }
            }

			EnvKESEndpoint:   "https://127.0.0.1:7373",
			EnvKESDefaultKey: "minio-key",
			EnvKESAPIKey:     "kes:v1:AGtR4PvKXNjz+/MlBX2Djg0qxwS3C4OjoDzsuFSQr82e",
		},
		IsPresent: true,
	},
	{ // 4
		Env: map[string]string{
			EnvKESEndpoint:   "https://127.0.0.1:7373",
			EnvKESDefaultKey: "minio-key",
			EnvKESClientKey:  "/tmp/client.key",
			EnvKESClientCert: "/tmp/client.crt",
		},
		IsPresent: true,
	},
	{ // 5

  protected Entry<K, V> entry(K key, V value) {
    return mapEntry(key, value);
  }

  @Override
  protected void expectContents(Collection<Entry<K, V>> expected) {
    // TODO: move this to invariant checks once the appropriate hook exists?
    super.expectContents(expected);
    for (Entry<K, V> entry : expected) {
      assertEquals(

		},
		config.HelpKV{
			Key:         config.Comment,
			Description: config.DefaultComment,
			Optional:    true,
			Type:        "sentence",
		},
		config.HelpKV{
			Key:         target.WebhookClientCert,
			Description: "client cert for Webhook mTLS auth",
			Optional:    true,
			Type:        "string",
			Sensitive:   true,
		},
		config.HelpKV{
			Key:         target.WebhookClientKey,

			<la:link href="/">
				<img src="${fe:url('/images/logo-top.png')}"
					alt="<la:message key="labels.header_brand_name" />" />
			</la:link>
		</div>
		<div class="notification">${notification}</div>
		<div class="card">
			<div class="card-body login-card-body">
				<p class="login-box-msg">
					<la:message key="labels.login" />
				</p>
				<%-- Message --%>
				<div>
					<la:info id="msg" message="false">

  }

  @Override
  public Set<V> get(@ParametricNullness K key) {
    return (Set<V>) super.get(key);
  }

  @Override
  public Set<V> removeAll(@CheckForNull Object key) {
    return (Set<V>) super.removeAll(key);
  }

  @Override
  public Set<V> replaceValues(@ParametricNullness K key, Iterable<? extends V> values) {
    return (Set<V>) super.replaceValues(key, values);
  }

  @Override

boundaries.height,\n    },\n  };\n\n  const sortedAreas = Object.keys(rects)\n    .map(key => ({\n      key,\n      ...rects[key],\n      area: getArea(rects[key]),\n    }))\n    .sort((a, b) => b.area - a.area);\n\n  const filteredAreas = sortedAreas.filter(\n    ({ width, height }) =>\n      width >= popper.clientWidth && height >= popper.clientHeight\n  );\n\n  const computedPlacement = filteredAreas.length > 0\n    ? filteredAreas[0].key\n    : sortedAreas[0].key;\n\n  const variation = placement.split('-')[1];\n\n...