python - bs 里 find() 问题

源码：

# coding: UTF-8
from bs4 import BeautifulSoup
html_doc = """


The Dormouse's story

Once upon a time there were three little sisters; and their names were
Elsie,
Lacie and
Tillie;
and they lived at the bottom of a well.

...
"""
soup = BeautifulSoup(html_doc, 'html.parser')
data = soup.find('p', {'class': 'story'})
print(data)

输出：

Once upon a time there were three little sisters; and their names were
Elsie,
Lacie and
Tillie;
and they lived at the bottom of a well.

问题：
我想爬取的是 p 标签下的 属性值为 story 的 class， 但是结果怎么出来有 a 标签呢？