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Python脚本无法从XML提取数据

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我正在尝试通过此XML文件解析和获取数据。但是我的代码没有按预期工作，而是什么也不显示。这是我正在使用的XML文件： 

<feed xml:base="http://data.treasury.gov/Feed.svc/">
  <title type="text">DailyTreasuryYieldCurveRateData</title>
  <id>
    http://data.treasury.gov/feed.svc/DailyTreasuryYieldCurveRateData
  </id>
  <updated>2019-11-04T07:15:32Z</updated>
  <link rel="self" title="DailyTreasuryYieldCurveRateData" href="DailyTreasuryYieldCurveRateData"/>
  <entry>
    <id>
      http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7258)
    </id>
    <title type="text"/>
    <updated>2019-11-04T07:15:32Z</updated>
    <author>
      <name/>
    </author>
    <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7258)"/>
    <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
    <content type="application/xml">
      <m:properties>
        <d:Id m:type="Edm.Int32">7258</d:Id>
        <d:NEW_DATE m:type="Edm.DateTime">2019-01-02T00:00:00</d:NEW_DATE>
        <d:BC_1MONTH m:type="Edm.Double">2.4</d:BC_1MONTH>
        <d:BC_2MONTH m:type="Edm.Double">2.4</d:BC_2MONTH>
        <d:BC_3MONTH m:type="Edm.Double">2.42</d:BC_3MONTH>
        <d:BC_6MONTH m:type="Edm.Double">2.51</d:BC_6MONTH>
        <d:BC_1YEAR m:type="Edm.Double">2.6</d:BC_1YEAR>
        <d:BC_2YEAR m:type="Edm.Double">2.5</d:BC_2YEAR>
        <d:BC_3YEAR m:type="Edm.Double">2.47</d:BC_3YEAR>
        <d:BC_5YEAR m:type="Edm.Double">2.49</d:BC_5YEAR>
        <d:BC_7YEAR m:type="Edm.Double">2.56</d:BC_7YEAR>
        <d:BC_10YEAR m:type="Edm.Double">2.66</d:BC_10YEAR>
        <d:BC_20YEAR m:type="Edm.Double">2.83</d:BC_20YEAR>
        <d:BC_30YEAR m:type="Edm.Double">2.97</d:BC_30YEAR>
        <d:BC_30YEARDISPLAY m:type="Edm.Double">2.97</d:BC_30YEARDISPLAY>
      </m:properties>
    </content>
  </entry>
  <entry>
  <id>
    http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7259)
  </id>
  <title type="text"/>
  <updated>2019-11-04T07:15:32Z</updated>
  <author>
    <name/>
  </author>
  <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7259)"/>
  <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
  <content type="application/xml">
    <m:properties>
      <d:Id m:type="Edm.Int32">7259</d:Id>
      <d:NEW_DATE m:type="Edm.DateTime">2019-01-03T00:00:00</d:NEW_DATE>
      <d:BC_1MONTH m:type="Edm.Double">2.42</d:BC_1MONTH>
      <d:BC_2MONTH m:type="Edm.Double">2.42</d:BC_2MONTH>
      <d:BC_3MONTH m:type="Edm.Double">2.41</d:BC_3MONTH>
      <d:BC_6MONTH m:type="Edm.Double">2.47</d:BC_6MONTH>
      <d:BC_1YEAR m:type="Edm.Double">2.5</d:BC_1YEAR>
      <d:BC_2YEAR m:type="Edm.Double">2.39</d:BC_2YEAR>
      <d:BC_3YEAR m:type="Edm.Double">2.35</d:BC_3YEAR>
      <d:BC_5YEAR m:type="Edm.Double">2.37</d:BC_5YEAR>
      <d:BC_7YEAR m:type="Edm.Double">2.44</d:BC_7YEAR>
      <d:BC_10YEAR m:type="Edm.Double">2.56</d:BC_10YEAR>
      <d:BC_20YEAR m:type="Edm.Double">2.75</d:BC_20YEAR>
      <d:BC_30YEAR m:type="Edm.Double">2.92</d:BC_30YEAR>
      <d:BC_30YEARDISPLAY m:type="Edm.Double">2.92</d:BC_30YEARDISPLAY>
    </m:properties>
  </content>
</entry>
<entry>
  <id>
    http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7260)
  </id>
  <title type="text"/>
  <updated>2019-11-04T07:15:32Z</updated>
  <author>
    <name/>
  </author>
  <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7260)"/>
  <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
  <content type="application/xml">
     <m:properties>
       <d:Id m:type="Edm.Int32">7260</d:Id>
       <d:NEW_DATE m:type="Edm.DateTime">2019-01-04T00:00:00</d:NEW_DATE>
       <d:BC_1MONTH m:type="Edm.Double">2.4</d:BC_1MONTH>
       <d:BC_2MONTH m:type="Edm.Double">2.42</d:BC_2MONTH>
       <d:BC_3MONTH m:type="Edm.Double">2.42</d:BC_3MONTH>
       <d:BC_6MONTH m:type="Edm.Double">2.51</d:BC_6MONTH>
       <d:BC_1YEAR m:type="Edm.Double">2.57</d:BC_1YEAR>
       <d:BC_2YEAR m:type="Edm.Double">2.5</d:BC_2YEAR>
       <d:BC_3YEAR m:type="Edm.Double">2.47</d:BC_3YEAR>
       <d:BC_5YEAR m:type="Edm.Double">2.49</d:BC_5YEAR>
       <d:BC_7YEAR m:type="Edm.Double">2.56</d:BC_7YEAR>
       <d:BC_10YEAR m:type="Edm.Double">2.67</d:BC_10YEAR>
       <d:BC_20YEAR m:type="Edm.Double">2.83</d:BC_20YEAR>
       <d:BC_30YEAR m:type="Edm.Double">2.98</d:BC_30YEAR>
       <d:BC_30YEARDISPLAY m:type="Edm.Double">2.98</d:BC_30YEARDISPLAY>
     </m:properties>
   </content>
 </entry>
</feed>

到目前为止，我已经尝试过： 

import requests as rq
import lxml.etree as ET

tree = ET.parse('DailyTreasuryYieldCurveRateData')
root = tree.getroot()

for ele in root.xpath('./entry/content/m:properties',namespaces={'m': 'http://schemas.microsoft.com/ado/2007/08/dataservices/scheme'}):
    print(ele)
    for foo in ele:
        print(foo.tag,foo.text)

但是，什么都不会显示。

我希望输出为：

NEW_DATE 2019-10-31T00:00:00
BC_1MONTH 1.59
BC_2MONTH 1.59
BC_3MONTH 1.59
BC_6MONTH 1.57
BC_1YEAR 1.54
BC_2YEAR 1.52
BC_3YEAR 1.52
BC_5YEAR 1.51
BC_7YEAR 1.6
BC_10YEAR 1.69
BC_20YEAR 2
BC_30YEAR 2.17
BC_30YEARDISPLAY 2.17

类似地，它应该循环到完整的XML并生成类似的输出！请告诉我我哪里错了。

SZLM668 回答：Python脚本无法从XML提取数据

您可以使用python-benedict（一个令人惊叹的dict子类）轻松完成此操作。

要安装它，只需运行pip install python-benedict，然后：

data_xml = """
<feed xml:base="http://data.treasury.gov/Feed.svc/">
  <title type="text">DailyTreasuryYieldCurveRateData</title>
  <id>
    http://data.treasury.gov/feed.svc/DailyTreasuryYieldCurveRateData
  </id>
  <updated>2019-11-04T07:15:32Z</updated>
  <link rel="self" title="DailyTreasuryYieldCurveRateData" href="DailyTreasuryYieldCurveRateData"/>
  <entry>
    <id>
      http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7258)
    </id>
    <title type="text"/>
    <updated>2019-11-04T07:15:32Z</updated>
    <author>
      <name/>
    </author>
    <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7258)"/>
    <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
    <content type="application/xml">
      <m:properties>
        <d:Id m:type="Edm.Int32">7258</d:Id>
        <d:NEW_DATE m:type="Edm.DateTime">2019-01-02T00:00:00</d:NEW_DATE>
        <d:BC_1MONTH m:type="Edm.Double">2.4</d:BC_1MONTH>
        <d:BC_2MONTH m:type="Edm.Double">2.4</d:BC_2MONTH>
        <d:BC_3MONTH m:type="Edm.Double">2.42</d:BC_3MONTH>
        <d:BC_6MONTH m:type="Edm.Double">2.51</d:BC_6MONTH>
        <d:BC_1YEAR m:type="Edm.Double">2.6</d:BC_1YEAR>
        <d:BC_2YEAR m:type="Edm.Double">2.5</d:BC_2YEAR>
        <d:BC_3YEAR m:type="Edm.Double">2.47</d:BC_3YEAR>
        <d:BC_5YEAR m:type="Edm.Double">2.49</d:BC_5YEAR>
        <d:BC_7YEAR m:type="Edm.Double">2.56</d:BC_7YEAR>
        <d:BC_10YEAR m:type="Edm.Double">2.66</d:BC_10YEAR>
        <d:BC_20YEAR m:type="Edm.Double">2.83</d:BC_20YEAR>
        <d:BC_30YEAR m:type="Edm.Double">2.97</d:BC_30YEAR>
        <d:BC_30YEARDISPLAY m:type="Edm.Double">2.97</d:BC_30YEARDISPLAY>
      </m:properties>
    </content>
  </entry>
  <entry>
  <id>
    http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7259)
  </id>
  <title type="text"/>
  <updated>2019-11-04T07:15:32Z</updated>
  <author>
    <name/>
  </author>
  <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7259)"/>
  <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
  <content type="application/xml">
    <m:properties>
      <d:Id m:type="Edm.Int32">7259</d:Id>
      <d:NEW_DATE m:type="Edm.DateTime">2019-01-03T00:00:00</d:NEW_DATE>
      <d:BC_1MONTH m:type="Edm.Double">2.42</d:BC_1MONTH>
      <d:BC_2MONTH m:type="Edm.Double">2.42</d:BC_2MONTH>
      <d:BC_3MONTH m:type="Edm.Double">2.41</d:BC_3MONTH>
      <d:BC_6MONTH m:type="Edm.Double">2.47</d:BC_6MONTH>
      <d:BC_1YEAR m:type="Edm.Double">2.5</d:BC_1YEAR>
      <d:BC_2YEAR m:type="Edm.Double">2.39</d:BC_2YEAR>
      <d:BC_3YEAR m:type="Edm.Double">2.35</d:BC_3YEAR>
      <d:BC_5YEAR m:type="Edm.Double">2.37</d:BC_5YEAR>
      <d:BC_7YEAR m:type="Edm.Double">2.44</d:BC_7YEAR>
      <d:BC_10YEAR m:type="Edm.Double">2.56</d:BC_10YEAR>
      <d:BC_20YEAR m:type="Edm.Double">2.75</d:BC_20YEAR>
      <d:BC_30YEAR m:type="Edm.Double">2.92</d:BC_30YEAR>
      <d:BC_30YEARDISPLAY m:type="Edm.Double">2.92</d:BC_30YEARDISPLAY>
    </m:properties>
  </content>
</entry>
<entry>
  <id>
    http://data.treasury.gov/Feed.svc/DailyTreasuryYieldCurveRateData(7260)
  </id>
  <title type="text"/>
  <updated>2019-11-04T07:15:32Z</updated>
  <author>
    <name/>
  </author>
  <link rel="edit" title="DailyTreasuryYieldCurveRateDatum" href="DailyTreasuryYieldCurveRateData(7260)"/>
  <category term="TreasuryDataWarehouseModel.DailyTreasuryYieldCurveRateDatum" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme"/>
  <content type="application/xml">
     <m:properties>
       <d:Id m:type="Edm.Int32">7260</d:Id>
       <d:NEW_DATE m:type="Edm.DateTime">2019-01-04T00:00:00</d:NEW_DATE>
       <d:BC_1MONTH m:type="Edm.Double">2.4</d:BC_1MONTH>
       <d:BC_2MONTH m:type="Edm.Double">2.42</d:BC_2MONTH>
       <d:BC_3MONTH m:type="Edm.Double">2.42</d:BC_3MONTH>
       <d:BC_6MONTH m:type="Edm.Double">2.51</d:BC_6MONTH>
       <d:BC_1YEAR m:type="Edm.Double">2.57</d:BC_1YEAR>
       <d:BC_2YEAR m:type="Edm.Double">2.5</d:BC_2YEAR>
       <d:BC_3YEAR m:type="Edm.Double">2.47</d:BC_3YEAR>
       <d:BC_5YEAR m:type="Edm.Double">2.49</d:BC_5YEAR>
       <d:BC_7YEAR m:type="Edm.Double">2.56</d:BC_7YEAR>
       <d:BC_10YEAR m:type="Edm.Double">2.67</d:BC_10YEAR>
       <d:BC_20YEAR m:type="Edm.Double">2.83</d:BC_20YEAR>
       <d:BC_30YEAR m:type="Edm.Double">2.98</d:BC_30YEAR>
       <d:BC_30YEARDISPLAY m:type="Edm.Double">2.98</d:BC_30YEARDISPLAY>
     </m:properties>
   </content>
 </entry>
</feed>
"""

现在可以初始化一个benedict实例：

from benedict import benedict as bdict

# this method accepts a data string,a file path or a file url
data = bdict.from_xml(data_xml)
# print(data.dump())

entries = data['feed.entry']
for entry in entries:
    props = bdict(bdict(entry)['content.m:properties'])
    # print(props.dump())

    for key,value in props.items():
        print(key,value['#text'])
    print('-----')

python-benedict在GitHub上经过了良好的测试，记录和开源：

https://github.com/fabiocaccamo/python-benedict

lxmlpython-3.xxml
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