我怎样才能把这个嵌套的JSON变成一个DataFrame呢？

import pandas as pd

# 从文件加载
with open('data.json', 'r') as file:
    data = pd.read_json(file)

# 或者从字符串加载
json_str = '{"key1":{"subkey1":"value1","subkey2":"value2"},"key2":{"subkey1":"value3"}}'
data = pd.read_json(json_str)

# 假设data是一个嵌套的字典
flattened_data = []

for key, value in data.items():
    for subkey, subvalue in value.items():
        flattened_data.append({'Key': key, 'Subkey': subkey, 'Value': subvalue})

df = pd.DataFrame(flattened_data)

print(df)

import pandas as pd

# 假设这是你的嵌套JSON数据
json_str = '{"key1":{"subkey1":"value1","subkey2":"value2"},"key2":{"subkey1":"value3"}}'

# 从字符串加载JSON数据
data = pd.read_json(json_str)

# 展平嵌套的JSON数据
flattened_data = []
for key, value in data.items():
    for subkey, subvalue in value.items():
        flattened_data.append({'Key': key, 'Subkey': subkey, 'Value': subvalue})

# 转换为DataFrame
df = pd.DataFrame(flattened_data)

# 打印DataFrame
print(df)