ScriptKiddo

import json

result = [1, 2, 3, 'Тестовый текст']

with open('result.json', 'w', encoding='utf8') as f:
    json.dump(result, f, ensure_ascii=False)

page = 1
test = f'test/page/{page}'

{"2000000003": {"amv": true, "amvl": true, "whoa": true}}
{"2000000004": {"amv": true, "amvl": true, "whoa": true}}

import json

target_id = '2000000004'

result = []
with open('test.json', encoding='UTF-8') as source, \
        open('test_out.json', 'w', encoding='UTF-8') as out:
    for line in source:
        parsed_json_line = json.loads(line)
        if target_id in parsed_json_line.keys():
            parsed_json_line[target_id]['amv'] = False
        out.write(f'{json.dumps(parsed_json_line)}\n')

import json

result = []
with open('test.json', encoding='UTF-8') as f:
    for line in f:
        result.append(json.loads(line))

target_id = '2000000004'

for i, item in enumerate(result):
    if target_id in item.keys():
        result[i][target_id]['amv'] = False



with open('test_out.json', 'w', encoding='UTF-8') as f:
    for item in result:
        f.write(f'{json.dumps(item)}\n')

{"2000000003": {"amv": true, "amvl": true, "whoa": true}}
{"2000000004": {"amv": false, "amvl": true, "whoa": true}}

import requests
import json
content = requests.get("http://rzhunemogu.ru/RandJSON.aspx?CType=1")
response_json = json.loads(content.text.replace('\r\n', '\\r\\n'))
print(response_json)

{'content': 'Смотpишь по телевизоpу pекламу - в ней pекламиpуют жуpнал. Покупаешь жуpнал - а там pеклама магазина. Идёшь в магазин - а там пpодают телевизоpы. Покупаешь телевизоp, включаешь - а там опять pеклама того же жуpнала. Где же выход?!'}