将CSV转换为JSON - Python时，空单元格变为"“

import csv
import json

import csv
import json

def csv_to_json(csv_file):
    json_data = []
    
    with open(csv_file, 'r') as file:
        reader = csv.DictReader(file, skipinitialspace=True)
        for row in reader:
            json_data.append(row)
    
    json_string = json.dumps(json_data)
    return json_string

csv_file = 'data.csv'
json_string = csv_to_json(csv_file)
print(json_string)