18 files declare their use of ModuleWeight

ConfigImporterTest.php in core/tests/Drupal/KernelTests/Core/Config/ConfigImporterTest.php
ConfigImportUITest.php in core/modules/config/tests/src/Functional/ConfigImportUITest.php
content_moderation_test_resave.install in core/modules/content_moderation/tests/modules/content_moderation_test_resave/content_moderation_test_resave.install
content_translation.install in core/modules/content_translation/content_translation.install
Installation functions for Content Translation module.
DrupalFlushAllCachesTest.php in core/tests/Drupal/KernelTests/Core/Common/DrupalFlushAllCachesTest.php
EntityUpdateTest.php in core/modules/editor/tests/src/Kernel/EntityUpdateTest.php
ExcludedModulesEventSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ExcludedModulesEventSubscriber.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
InstallerConfigDirectoryTestBase.php in core/tests/Drupal/FunctionalTests/Installer/InstallerConfigDirectoryTestBase.php
MenuLinkContentCacheabilityBubblingTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentCacheabilityBubblingTest.php
module.inc in core/includes/module.inc
API for loading and interacting with Drupal modules.
ModuleHandlerTest.php in core/modules/system/tests/src/Kernel/Extension/ModuleHandlerTest.php
module_handler_test_multiple.install in core/modules/system/tests/modules/module_handler_test_multiple/module_handler_test_multiple.install
module_handler_test_multiple_child.install in core/modules/system/tests/modules/module_handler_test_multiple/module_handler_test_multiple_child/module_handler_test_multiple_child.install
PathAliasMenuLinkContentTest.php in core/modules/menu_link_content/tests/src/Kernel/PathAliasMenuLinkContentTest.php
RebuildScriptTest.php in core/modules/system/tests/src/Functional/UpdateSystem/RebuildScriptTest.php
UpdatePathNewDependencyTest.php in core/modules/system/tests/src/Functional/UpdateSystem/UpdatePathNewDependencyTest.php
views.install in core/modules/views/views.install
Contains install and update functions for Views.

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