如何在python中遍历json树

您可以将json字符串解码为Python数组并对其进行迭代：

import json


json_string = '''[{"image": {"alt": "Coffee", "assetId": "24073832", "assetName": "42227-230294--Food_Coffee_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/coffee/1086446?povid=976759+%7C+2018-12-26+%7C+Food%20Coffee%20Shop%20by%20Category%20Tile%201", "rawValue": "/cp/coffee/1086446", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Coffee%20Shop%20by%20Category%20Tile%201"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-4fec/k2-_d0c27367-0903-424d-9ed7-25ff31ed2078.v1.jpg", "title": "Coffee", "width": "320", "size": "48986", "contentType": "image/jpg", "uid": "EVz8WxyK"}, "uid": "KzzTghKO"}, {"image": {"alt": "Meal Solutions, Grains & Pasta", "assetId": "16511345", "assetName": "41423-209368-Food-Meals_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/meal-solutions-grains-pasta/976794?povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Shop%20by%20Category%20Tile%202", "rawValue": "/cp/meal-solutions-grains-pasta/976794", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Shop%20by%20Category%20Tile%202"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-b006/k2-_9c1d502f-c08d-4591-a734-b205d0ffe45b.v1.jpg", "title": "Meal Solutions, Grains & Pasta", "width": "320", "size": "21747", "contentType": "image/jpg", "uid": "a0xEKGc1"}, "uid": "Sa4hkgg8"}, {"image": {"alt": "Snacks", "assetId": "16511346", "assetName": "41423-209369-Food_Snacks_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/snacks-cookies-chips/976787?povid=976759+%7C+2018-12-26+%7C+Food%20Snack%20Shop%20by%20Category%20Tile%203", "rawValue": "/cp/snacks-cookies-chips/976787", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Snack%20Shop%20by%20Category%20Tile%203"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-66f5/k2-_a622db4c-a789-4f03-bf16-440ad12efcd8.v1.jpg", "title": "Snacks", "width": "320", "size": "22038", "contentType": "image/jpg", "uid": "iYpawUR8"}, "uid": "KN0Y6XJk"}, {"image": {"alt": "Beverages", "assetId": "31886230", "assetName": "42592-239546 Food Beverages Featured Category Tile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/beverages/976782?povid=976759+%7C+2018-12-26+%7C+Food%20Beverages%20Shop%20by%20Category%20Tile%204", "rawValue": "/cp/beverages/976782", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Beverages%20Shop%20by%20Category%20Tile%204"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-b691/k2-_95cdb69e-5175-408a-b18e-7c8a4902da65.v1.jpg", "title": "Beverages", "width": "320", "size": "21411", "contentType": "image/jpg", "uid": "YDQP7Zs1"}, "uid": "eronFjMz"}, {"image": {"alt": "Chocolate, Candy & Gum", "assetId": "16511348", "assetName": "41423-209371-Food_Candy_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/chocolate-candy-gum/1096070?povid=976759+%7C+2018-12-26+%7C+Food%20Candy%20Shop%20by%20Category%20Tile%205", "rawValue": "/cp/chocolate-candy-gum/1096070", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Candy%20Shop%20by%20Category%20Tile%205"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-26df/k2-_0e1ed3ed-51c5-4d55-a4b3-64d5beab75c4.v1.jpg", "title": "Chocolate, Candy & Gum", "width": "320", "size": "24819", "contentType": "image/jpg", "uid": "khYex7Z3"}, "uid": "N57hxj54"}, {"image": {"alt": "Condiments", "assetId": "16511349", "assetName": "41423-209372-Food_Condiments_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/976786?povid=976759+%7C+2018-12-26+%7C+Food%20Condiments%20Shop%20by%20Category%20Tile%206", "rawValue": "/cp/976786", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Condiments%20Shop%20by%20Category%20Tile%206"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-c487/k2-_0b0b1864-112c-4323-9474-9556739bf3b5.v1.jpg", "title": "Condiments", "width": "320", "size": "12514", "contentType": "image/jpg", "uid": "rxFVAq08"}, "uid": "Ych6vXbE"}, {"image": {"alt": "Baking", "assetId": "16511350", "assetName": "41423-209373-Food_Baking_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/baking/976780?povid=976759+%7C+2018-12-26+%7C+Food%20Baking%20Shop%20by%20Category%20Tile%207", "rawValue": "/cp/baking/976780", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Baking%20Shop%20by%20Category%20Tile%207"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-26b5/k2-_7ad38e98-0ccd-479f-9bfa-1d4d4dfe90a2.v1.jpg", "title": "Baking", "width": "320", "size": "18935", "contentType": "image/jpg", "uid": "pI4YqGyq"}, "uid": "07562lCu"}, {"image": {"alt": "Breakfast & Cereal", "assetId": "16511351", "assetName": "41423-209374-Food_Breakfast_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/cp/breakfast-food-cereal/976783?povid=976759+%7C+2018-12-26+%7C+Food%20Breakfast%20&%20Cereal%20Shop%20by%20Category%20Tile%208", "rawValue": "/cp/breakfast-food-cereal/976783", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Breakfast%20&%20Cereal%20Shop%20by%20Category%20Tile%208"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-f53c/k2-_3a8d9006-e514-48b7-ad81-c4a70a8d39e9.v1.jpg", "title": "Breakfast & Cereal", "width": "320", "size": "24847", "contentType": "image/jpg", "uid": "PQUXkqiQ"}, "uid": "gJmzhaYu"}, {"image": {"alt": "Food Gift Baskets", "assetId": "16511356", "assetName": "41423-209379-Food_GiftBaskets_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/browse/food/gift-baskets/976759_1089004?povid=976759+%7C+2018-12-26+%7C+Food%20Gift%20Baskets%20Shop%20by%20Category%20Tile%209&povid=976759+%7C+2018-12-26+%7C+Food%20Gift%20Baskets%20Shop%20by%20Category%20Tile%209", "rawValue": "/browse/food/gift-baskets/976759_1089004?povid=976759+%7C+2018-12-26+%7C+Food%20Gift%20Baskets%20Shop%20by%20Category%20Tile%209", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Gift%20Baskets%20Shop%20by%20Category%20Tile%209"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-8e1b/k2-_3e651309-806d-4633-95f6-ec015c783759.v1.jpg", "title": "Food Gift Baskets", "width": "320", "size": "19695", "contentType": "image/jpg", "uid": "nEwGTdfg"}, "uid": "ommZYX3q"}, {"image": {"alt": "Emergency Food", "assetId": "16511354", "assetName": "41423-209377-Food_EmergencyFood_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/browse/meal-solutions-grains-pasta/emergency-food/976759_976794_1094144?povid=976759+%7C+2018-12-26+%7C+Food%20Emergency%20Food%20Shop%20by%20Category%20Tile%2010&povid=976759+%7C+2018-12-26+%7C+Food%20Emergency%20Food%20Shop%20by%20Category%20Tile%2010", "rawValue": "/browse/meal-solutions-grains-pasta/emergency-food/976759_976794_1094144?povid=976759+%7C+2018-12-26+%7C+Food%20Emergency%20Food%20Shop%20by%20Category%20Tile%2010", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Emergency%20Food%20Shop%20by%20Category%20Tile%2010"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-369d/k2-_5fc9cbf1-4b2e-47ba-a35c-d5016d80a0a1.v1.jpg", "title": "Emergency Food", "width": "320", "size": "12594", "contentType": "image/jpg", "uid": "L0VEhGaa"}, "uid": "EV4aR1IJ"}, {"image": {"alt": "Organic Foods", "assetId": "16511352", "assetName": "41423-209375-Food_Organic_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/browse/food/organic-foods/976759_1228024?povid=976759+%7C+2018-12-26+%7C+Food%20Organic%20Foods%20Shop%20by%20Category%20Tile%2010&povid=976759+%7C+2018-12-26+%7C+Food%20Organic%20Foods%20Shop%20by%20Category%20Tile%2010", "rawValue": "/browse/food/organic-foods/976759_1228024?povid=976759+%7C+2018-12-26+%7C+Food%20Organic%20Foods%20Shop%20by%20Category%20Tile%2010", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Organic%20Foods%20Shop%20by%20Category%20Tile%2010"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-e889/k2-_025af29b-a175-43d9-a7f1-8a41b7f595d8.v1.jpg", "title": "Organic Foods", "width": "320", "size": "14996", "contentType": "image/jpg", "uid": "VodpOeXr"}, "uid": "6bskKrLd"}, {"image": {"alt": "Gluten-Free Foods", "assetId": "16511353", "assetName": "41423-209376-Food_Gluten-Free_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/browse/food/gluten-free-foods/976759_1228023?povid=976759+%7C+2018-12-26+%7C+Food%20Gluten%20Free%20Shop%20by%20Category%20Tile%2010&povid=976759+%7C+2018-12-26+%7C+Food%20Gluten%20Free%20Shop%20by%20Category%20Tile%2010", "rawValue": "/browse/food/gluten-free-foods/976759_1228023?povid=976759+%7C+2018-12-26+%7C+Food%20Gluten%20Free%20Shop%20by%20Category%20Tile%2010", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Gluten%20Free%20Shop%20by%20Category%20Tile%2010"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-40b6/k2-_d4adeded-bc5a-4141-8ff5-484e5a57af7b.v1.jpg", "title": "Gluten-Free Foods", "width": "320", "size": "11866", "contentType": "image/jpg", "uid": "-BPKl3mO"}, "uid": "DxMgKndk"}, {"image": {"alt": "Meal Delivery Services", "assetId": "16511355", "assetName": "41423-209378-Food_MealKits_FeaturedCategoryTile_V1.jpg", "clickThrough": {"type": "url", "value": "/browse/food/meal-kits-specialty-food-boxes/976759_7123943?povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Delivery%20Services%20Shop%20by%20Category%20Tile%2010&povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Delivery%20Services%20Shop%20by%20Category%20Tile%2010", "rawValue": "/browse/food/meal-kits-specialty-food-boxes/976759_7123943?povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Delivery%20Services%20Shop%20by%20Category%20Tile%2010", "tag": "povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Delivery%20Services%20Shop%20by%20Category%20Tile%2010"}, "height": "320", "src": "https://i5.walmartimages.com/dfw/4ff9c6c9-bed9/k2-_b82a8177-43e5-45d2-bc92-1dccd94d1e5d.v1.jpg", "title": "Meal Delivery Services", "width": "320", "size": "20720", "contentType": "image/jpg", "uid": "XAyoF2GU"}, "uid": "MeJ6LK_Z"}]'''
data = json.loads(json_string)

for image in data:
    print(image['image']['alt'])
    print(image['image']['src'])
    print(image['image']['clickThrough']['value'])
    print('-' * 80)

印刷品：

咖啡

https://i5.walmartimages.com/dfw/4ff9c6c9-4fec/k2-_d0c27367-0903-424d-9ed7-25ff31ed2078.v1.jpg
/cp/coffee/1086446?povid=976759+%7C+2018-12-26+%7C+Food%20Coffee%20Shop%20by%20Category%20Tile%201
--------------------------------------------------------------------------------
Meal Solutions, Grains & Pasta
https://i5.walmartimages.com/dfw/4ff9c6c9-b006/k2-_9c1d502f-c08d-4591-a734-b205d0ffe45b.v1.jpg
/cp/meal-solutions-grains-pasta/976794?povid=976759+%7C+2018-12-26+%7C+Food%20Meal%20Shop%20by%20Category%20Tile%202
--------------------------------------------------------------------------------

...and so on.