我发现了一个快速简单的方法来格式化和打印一个xml文件:

import xml.etree.ElementTree as ET

xmlTree = ET.parse('your XML file')
xmlRoot = xmlTree.getroot()
xmlDoc =  ET.tostring(xmlRoot, encoding="unicode")

print(xmlDoc)

Outuput:

<root>
  <child>
    <subchild>.....</subchild>
  </child>
  <child>
    <subchild>.....</subchild>
  </child>
  ...
  ...
  ...
  <child>
    <subchild>.....</subchild>
  </child>
</root>

另一个解决方案是借用这个缩进函数，用于自2.5以来内置在Python中的ElementTree库。 下面是它的样子:

from xml.etree import ElementTree

def indent(elem, level=0):
    i = "\n" + level*"  "
    j = "\n" + (level-1)*"  "
    if len(elem):
        if not elem.text or not elem.text.strip():
            elem.text = i + "  "
        if not elem.tail or not elem.tail.strip():
            elem.tail = i
        for subelem in elem:
            indent(subelem, level+1)
        if not elem.tail or not elem.tail.strip():
            elem.tail = j
    else:
        if level and (not elem.tail or not elem.tail.strip()):
            elem.tail = j
    return elem        

root = ElementTree.parse('/tmp/xmlfile').getroot()
indent(root)
ElementTree.dump(root)

我用几行代码解决了这个问题，打开文件，通过它并添加缩进，然后再次保存它。我使用的是小的xml文件，不想添加依赖项，也不想为用户安装更多的库。总之，这是我最后得出的结论:

    f = open(file_name,'r')
    xml = f.read()
    f.close()

    #Removing old indendations
    raw_xml = ''        
    for line in xml:
        raw_xml += line

    xml = raw_xml

    new_xml = ''
    indent = '    '
    deepness = 0

    for i in range((len(xml))):

        new_xml += xml[i]   
        if(i<len(xml)-3):

            simpleSplit = xml[i:(i+2)] == '><'
            advancSplit = xml[i:(i+3)] == '></'        
            end = xml[i:(i+2)] == '/>'    
            start = xml[i] == '<'

            if(advancSplit):
                deepness += -1
                new_xml += '\n' + indent*deepness
                simpleSplit = False
                deepness += -1
            if(simpleSplit):
                new_xml += '\n' + indent*deepness
            if(start):
                deepness += 1
            if(end):
                deepness += -1

    f = open(file_name,'w')
    f.write(new_xml)
    f.close()

这对我来说很有用，也许有人会用到它:)

如果由于某种原因你无法获得其他用户提到的任何Python模块，我建议使用以下Python 2.7解决方案:

import subprocess

def makePretty(filepath):
  cmd = "xmllint --format " + filepath
  prettyXML = subprocess.check_output(cmd, shell = True)
  with open(filepath, "w") as outfile:
    outfile.write(prettyXML)

据我所知，这种解决方案适用于安装了xmllint包的基于unix的系统。

import xml.dom.minidom

dom = xml.dom.minidom.parse(xml_fname) # or xml.dom.minidom.parseString(xml_string)
pretty_xml_as_string = dom.toprettyxml()

from lxml import etree
import xml.dom.minidom as mmd

xml_root = etree.parse(xml_fiel_path, etree.XMLParser())

def print_xml(xml_root):
    plain_xml = etree.tostring(xml_root).decode('utf-8')
    urgly_xml = ''.join(plain_xml .split())
    good_xml = mmd.parseString(urgly_xml)
    print(good_xml.toprettyxml(indent='    ',))

它的工作良好的xml与中国!