Python 使用Beautiful Soup获取第二个srcset属性

只需 Select 所有<source>个标签并使用常规索引即可:

from bs4 import BeautifulSoup

html_source = """\
<picture class="card-picture ratio ratio-4x3">
<source srcset="/shop/media/L004D000_picture.PNG?context=bWFzdGVyfGltYWdlc3wzMDE3NTN8aW1hZ2UvcG5nfGgwMS9oMjcvODg0ODIyMDYxODc4Mi9MMDA0RDAwMF9waWN0dXJlLlBOR3wyZjRiZWE1NDU2MWU1MjUzMzU5MjAwNGVlYmIzY2MwNGQzODExMDI3NjNkMDE3YjQ4NGMwNjFlMGVkNTU2OWIy&amp;rmode=pad&amp;width=640&amp;rmode=pad&amp;width=640&amp;format=webp" type="image/webp"/>
<source srcset="/shop/media/L004D000_picture.PNG?context=bWFzdGVyfGltYWdlc3wzMDE3NTN8aW1hZ2UvcG5nfGgwMS9oMjcvODg0ODIyMDYxODc4Mi9MMDA0RDAwMF9waWN0dXJlLlBOR3wyZjRiZWE1NDU2MWU1MjUzMzU5MjAwNGVlYmIzY2MwNGQzODExMDI3NjNkMDE3YjQ4NGMwNjFlMGVkNTU2OWIy&amp;rmode=pad&amp;width=640&amp;rmode=pad&amp;width=640" type="image/jpeg"/>
<img alt="" class="card-img object-fit-contain is-contain" loading="lazy" src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7">
</img>
</picture>"""

soup = BeautifulSoup(html_source, "html.parser")

results = soup.select("picture")

for result in results:
    second_img = result.select("source")[1]
    print(second_img)

输出:

<source srcset="/shop/media/L004D000_picture.PNG?context=bWFzdGVyfGltYWdlc3wzMDE3NTN8aW1hZ2UvcG5nfGgwMS9oMjcvODg0ODIyMDYxODc4Mi9MMDA0RDAwMF9waWN0dXJlLlBOR3wyZjRiZWE1NDU2MWU1MjUzMzU5MjAwNGVlYmIzY2MwNGQzODExMDI3NjNkMDE3YjQ4NGMwNjFlMGVkNTU2OWIy&amp;rmode=pad&amp;width=640&amp;rmode=pad&amp;width=640" type="image/jpeg"/>

或: Select image/jpeg:

for result in results:
    jpeg_img = result.select_one('source[type="image/jpeg"]')
    print(jpeg_img)

或者如果您想要第一个jpeg或png:

for result in results:
    img = result.select_one('source[type="image/jpeg"], source[type="image/png"]')
    print(img)