我想使用 PHP 解析來自 onesignal API 的響應。以下是 API 響應的結構。我想打印唯一的某些參數。我怎樣才能做到這一點？{    "adm_big_picture": "",    "adm_group": "",    "adm_group_message": {        "en": ""    },    "adm_large_icon": "",    "adm_small_icon": "",    "adm_sound": "",    "spoken_text": {},    "alexa_ssml": null,    "alexa_display_title": null,    "amazon_background_data": false,    "android_accent_color": "FF9900FF",    "android_group": "group key",    "android_group_message": {        "en": "group message for Android 6.0 and older"    },    "android_led_color": null,    "android_sound": null,    "android_visibility": 1,    "app_id": "3beb3078-e0f1-4629-af17-fde833b9f716",    "big_picture": "https://img.onesignal.com/n/37326fcc-2baa-45da-891c-ca9454a64957.png",    "buttons": null,    "canceled": false,    "chrome_big_picture": "",    "chrome_icon": "",    "chrome_web_icon": "https://picture-resource.com/icon-image.png",    "chrome_web_image": "https://picture-resource.com/image.png",    "chrome_web_badge": "https://picture-resource.com/badge.png",    "content_available": false,    "contents": {        "en": "English Message"    },    "converted": 1,    "data": {        "additional": "data",        "campaign": "25"    },    "delayed_option": "immediate",    "delivery_time_of_day": "2:32PM",    "errored": 4,    "excluded_segments": [],    "failed": 0,    "firefox_icon": "https://picture-resource.com/firefox_icon.png",    "global_image": "https://link-to-your-image.com/image-resource-file.png",    "headings": {        "en": "English Message Title ??"    },    "id": "fd1723c6-bfaf-4f53-b4f4-0408ff43e18a",    "include_player_ids": null,    "include_external_user_ids": null,    "included_segments": [        "Subscribed Users"    ],我只想打印某些參數，以便我可以做進一步的處理。但我無法解析響應。