python报错误：json.decoder.JSONDecodeError: Unexpected UTF-8 BOM (decode using utf-8-sig)

源码：
with open(os.getcwd() + "\\category.txt", encoding='utf-8') as file_read:
    for line in file_read.readlines():
        categorys.append(json.loads(line.strip()))
    file_read.close()
print(categorys)

改为：

with open(os.getcwd() + "\\category.txt", encoding='utf-8_sig') as file_read:
    for line in file_read.readlines():  # 依次读取每行
        categorys.append(json.loads(line.strip()))
    file_read.close()
print(categorys)