如何使用 Python 提取/解析字典元素？

Question

I would like to extract the 00s from the decades, but all attempts are not pulling the intended results.

Here is part of what my XML file looks like, save as gorillas_catalog.xml.

<CATALOG>
    <CD decade="00s">
        <TITLE>Gorillaz</TITLE>
        <ARTIST>Gorillaz</ARTIST>
        <COUNTRY>UK</COUNTRY>
        <COMPANY>Virgin</COMPANY>
        <PRICE>10.90</PRICE>
        <YEAR>2001</YEAR>
    </CD>
    <CD decade="00s">
        <TITLE>Demon Days</TITLE>
        <ARTIST>Gorillaz</ARTIST>
        <COUNTRY>UK</COUNTRY>
        <COMPANY>Parlaphone</COMPANY>
        <PRICE>9.90</PRICE>
        <YEAR>1988</YEAR>
    </CD>

My intended results are something like this:

Title: Gorillaz, Album: Gorillaz, Decade: 00s
Title: Gorillaz, Album: Demon Days, Decade: 00s

So on and so forth through the rest of my XML file.

I tested each part and got as far as this code below:

import xml.etree.ElementTree as ET

tree = ET.parse("gorillaz_catalog.xml")
root = tree.getroot()

for ARTIST in root.iter("ARTIST"):
    print("Artist:", ARTIST.text)

for TITLE in root.iter("TITLE"):
    print("Title:", TITLE.text)

for decade in root.iter("CD"):
    print("Decade:", decade.attrib)

For decade I am receiving Decade: {'decade': '00s'} where I just want 00s .

Then I tried to loop everything to get my intended results (after commenting out the 3 for statements above).

for ARTIST in root.iter("ARTIST"):
    for TITLE in root.iter("TITLE"):
        for decade in root.iter("CD"):
            print("Artist:", ARTIST.text,", Title:", TITLE.text, ", Decade:", decade.attrib)

The results I got are looping through 20 times to many:

Artist: Gorillaz , Album: Gorillaz , Decade: {'decade': 00s'}

twenty times (that's the number number of records in the file), then

Artist: Gorillaz , Album: Demon Days , Decade: {'decade': '80s'}

twenty times...

So this gives me the line I want, but I don't need them 20 times each.

2. Clearly my nested loop is incorrect, so how do I get it to produce my intended lines? I'm thinking I might need to put the items in a dictionary list, but I'm not too familiar with accomplishing this.

Answer 1

I think you made it a little too complicated; try it with another library plus xpath:

import lxml.html as lh

cds = """[your html above]"""

doc = lh.fromstring(cds)
for cd in doc.xpath('//cd'):
    decade = cd.xpath('./@decade')[0]
    title = cd.xpath('./title/text()')[0]
    artist = cd.xpath('./artist/text()')[0]
    print("Title: "+title+", Artist: "+artist+", Decade: "+decade)

Output:

Title: Gorillaz, Artist: Gorillaz, Decade: 00s
Title: Demon Days, Artist: Gorillaz, Decade: 00s

Answer 2

Here is my final code after reviewing a bit more documentation after posting. Thank you all for the advice.

import xml.etree.ElementTree as ET

tree = ET.parse("gorillaz_catalog.xml")
root = tree.getroot()

for item in tree.iterfind("CD"):
    artist = item.findtext("ARTIST")
    title = item.findtext("TITLE")
    decade = item.get("decade")
    print(f"Artist: {artist}, Album: {title}, Decade: {decade}")

Output:

> Title: Gorillaz, Album: Gorillaz, Decade: 00s
> Title: Gorillaz, Album: Demon Days, Decade: 00s