How to apply a Drupal / contrib patch with the cweagans/composer-patches package

composer require cweagans/composer-patches

...
"extra": {
     "drupal-scaffold": {
         "locations": {
             "web-root": "web/"
         }
     },//This is where you apply the patches
     "enable-patching": true,
     "patches": {
         "drupal/username_policy": {
             "username policy default value issue": "https://www.drupal.org/files/issues/2019-12-20/username_policy_default_username_patch_0.patch"
         },
         "drupal/core": {
             "Fix Admin Toolbar Language Issue": "https://www.drupal.org/files/issues/2018-04-12/2313309-44.patch",
             "FIx Permissions Translate Content Can Edit Issue": "https://www.drupal.org/files/issues/2019-12-03/allow-users-to-translate-editable-content-2972308-41.patch"
         }
      },

{
  "require": {
    "cweagans/composer-patches": "~1.0",
    "drupal/core-recommended": "^8.8",
  },
  "config": {
    "preferred-install": "source"
  },
  "extra": {
    "patches": {
      "drupal/core": {
        "Add startup configuration for PHP server": "https://www.drupal.org/files/issues/add_a_startup-1543858-30.patch"
      }
    }
  }
}

{
  "require": {
    "cweagans/composer-patches": "~1.0",
    "drupal/core-recommended": "^8.8",
  },
  "config": {
    "preferred-install": "source"
  },
  "extra": {
    "patches-file": "local/path/to/your/composer.patches.json"
  }
}

{
  "patches": {
    "vendor/project": {
      "Patch title": "http://example.com/url/to/patch.patch"
    }
  }
}