如何使用可选的中间名和姓氏来后缀撇号？

def add_suffix(first_name, middle_name=None, last_name):
    if middle_name:
        full_name = f"{first_name} {middle_name} {last_name}"
    else:
        full_name = f"{first_name} {last_name}"
    
    return f"{full_name}'"

# 示例
print(add_suffix("John", "Michael", "Doe"))  # 输出：John Michael Doe'
print(add_suffix("Jane", None, "Smith"))  # 输出：Jane Smith'