掌握BeautifulSoup标签树的导航

子标签和后代标签：children()、descendants()

兄弟标签：

next_siblings()、next_sibling()

previous_siblings()、previous_sibling()

父标签：parent()

from urllib.request import urlopen
from bs4 import BeautifulSoup

html = urlopen("http://www.pythonscraping.com/pages/page3.html")
bsObj = BeautifulSoup(html, "html.parser")

for child in bsObj.find("table", {"id" : "giftList"}).children:
    print(child)

for sibling in bsObj.find("table", {"id" : "giftList"}).tr.next_siblings:
    print(sibling)

print(bsObj.find("img", {"src":"../img/gifts/img1.jpg"}).parent.previous_sibling.get_text())