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How to use ElemenTree for reading XML files in Python?

I've got an XML file which looks like this:
<?xml version="1.0"?>
-<Object>
<ID>Object_01</ID>
<Location>Manchester</Location>
<Date>01-01-2020</Date>
<Time>15u59m05s</Time>
-<Max_25Hz>
<25Hz>0.916631065043311</25Hz>
<25Hz>0.797958008447961</25Hz>
</Max_25Hz>
-<Max_75Hz>
<75Hz>1.96599232706463</75Hz>
<75Hz>1.48317837078523</75Hz>
</Max_75Hz>
</Object>
I still don't really understand the difference between attributes and text. With below code I tried to receive all the values using text.
import xml.etree.ElementTree as ET
root = r'c:\data\FF\Desktop\My_files\XML-files\Object_01.xml'
tree = ET.parse(root)
root = tree.getroot()
for elem in root:
for subelem in elem:
print(subelem.text)
Expected output:
Object_01
Manchester
01-01-2020
15u59m05s
0.916631065043311
0.797958008447961
1.96599232706463
1.48317837078523
Received output:
0.916631065043311
0.797958008447961
1.96599232706463
1.48317837078523
I tried to do to same with .attributes in the hope to receive all the 'column' names but then I received:
{}
{}
{}
{}

You can access them directly above the for-loop.
Ex:
tree = ET.ElementTree(ET.fromstring(X))
root = tree.getroot()
for elem in root:
print(elem.text) #! Access them Here
for subelem in elem:
print(subelem.text)
Output:
Object_01
Manchester
01-01-2020
15u59m05s
0.916631065043311
0.797958008447961
1.96599232706463
1.48317837078523

You could give a try to https://github.com/martinblech/xmltodict.
It is almost a replacement for json module. This allows to read an xml file into a python dict. This simplifies greatly accessing the xml content.
Something like:
from xmldict import *
root = r'c:\data\FF\Desktop\My_files\XML-files\Object_01.xml'
with open(root) as file:
xmlStr = file.read()
xmldict = xml.parse(xmlStr)
print (xmldict['Object']['Id'])

Problem on using lxml with tostring and pretty_print

I have read some of the answers for related questions, but none of them is directly related with lxml tostring and pretty_print.
I am using lxml and trying to create a xml file on Python 3.6.
The problem I found is that elements are not wrapped and ordered by parent element and believe it is related with the "pretty_print" option.
What I need to achieve is:
<root>
<element1></element1>
<element2></element2>
<child1></child1>
<child2></child2>
</root>
The result I get is:
<root><element1></element1><element2></element2><child1></child1><child2></child2></root>
Part of the code I am using:
from lxml import etree as et
CompanyID = "Company Identification"
TaxRegistrationNumber = "Company Reg. Number"
TaxAccountingBasis = "File Tipe"
CompanyName = "Company Name"
BusinessName = "Business Name"
root = et.Element("root")
header = et.SubElement(root, 'Header')
header.tail = '\n'
data = (
('CompanyID', str(CompanyID)),
('TaxRegistrationNumber', str(TaxRegistrationNumber)),
('TaxAccountingBasis', str(TaxAccountingBasis)),
('CompanyName', str(CompanyName)),
('BusinessName', str(BusinessName)),
)
for tag, value in data:
if value is None :
continue
et.SubElement(header, tag).text=value
xml_txt = et.tostring(root, pretty_print=True, encoding="UTF-8")
print(xml_txt)
If I print the elements with no data into it, it works fine and the "pretty_print" works fine.
If I add data to each of the elements (using the above variables), the "pretty_print" does not work and the structure gets messed up.
What could be wrong?

I found it.
I have removed the "header.tail = '\n'" from the code and it's working now.
root = et.Element("root")
header = et.SubElement(root, 'Header')
#header.tail = '\n'
Thank you all

Finding element in xml with python

I am trying to parse XML before converting it's content into lists and then into CSV. Unfortunately, I think my search terms for finding the initial element are failing, causing subsequent searches further down the hierarchy. I am new to XML, so I've tried variations on namespace dictionaries and including the namespace references... The simplified XML is given below:
<?xml version="1.0" encoding="utf-8"?>
<StationList xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:add="http://www.govtalk.gov.uk/people/AddressAndPersonalDetails"
xmlns:com="http://nationalrail.co.uk/xml/common" xsi:schemaLocation="http://internal.nationalrail.co.uk/xml/XsdSchemas/External/Version4.0/nre-station-v4-0.xsd"
xmlns="http://nationalrail.co.uk/xml/station">
<Station xsi:schemaLocation="http://internal.nationalrail.co.uk/xml/XsdSchemas/External/Version4.0/nre-station-v4-0.xsd">
<ChangeHistory>
<com:ChangedBy>spascos</com:ChangedBy>
<com:LastChangedDate>2018-11-07T00:00:00.000Z</com:LastChangedDate>
</ChangeHistory>
<Name>Aber</Name>
</Station>​
The Code I am using to try to extract the com/...xml/station / ChangedBy element is below
tree = ET.parse(rootfilepath + "NRE_Station_Dataset_2019_raw.xml")
root = tree.getroot()
#get at the tags and their data
#for elem in tree.iter():
# print(f"this the tag {elem.tag} and this is the data: {elem.text}")
#open file for writing
station_data = open(rootfilepath + 'station_data.csv','w')
csvwriter = csv.writer(station_data)
station_head = []
count = 0
#inspiration for this code: http://blog.appliedinformaticsinc.com/how-to- parse-and-convert-xml-to-csv-using-python/
#this is where it goes wrong; some combination of the namespace and the tag can't find anything in line 27, 'StationList'
for member in root.findall('{http://nationalrail.co.uk/xml/station}Station'):
station = []
if count == 0:
changedby = member.find('{http://nationalrail.co.uk/xml/common}ChangedBy').tag
station_head.append(changedby)
name = member.find('{http://nationalrail.co.uk/xml/station}Name').tag
station_head.append(name)
count = count+1
changedby = member.find('{http://nationalrail.co.uk/xml/common}ChangedBy').text
station.append(changedby)
name = member.find('{http://nationalrail.co.uk/xml/station}Name').text
station.append(name)
csvwriter.writerow(station)
I have tried:
using dictionaries of namespaces but that results in nothing being found at all
using hard coded namespaces but that results in "Attribute Error: 'NoneType' object has no attribute 'tag'
Thanks in advance for all and any assistance.

First of all your XML is invalid (</StationList> is absent at the end of a file).
Assuming you have valid XML file:
<?xml version="1.0" encoding="utf-8"?>
<StationList xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:add="http://www.govtalk.gov.uk/people/AddressAndPersonalDetails"
xmlns:com="http://nationalrail.co.uk/xml/common" xsi:schemaLocation="http://internal.nationalrail.co.uk/xml/XsdSchemas/External/Version4.0/nre-station-v4-0.xsd"
xmlns="http://nationalrail.co.uk/xml/station">
<Station xsi:schemaLocation="http://internal.nationalrail.co.uk/xml/XsdSchemas/External/Version4.0/nre-station-v4-0.xsd">
<ChangeHistory>
<com:ChangedBy>spascos</com:ChangedBy>
<com:LastChangedDate>2018-11-07T00:00:00.000Z</com:LastChangedDate>
</ChangeHistory>
<Name>Aber</Name>
</Station>​
</StationList>
Then you can convert your XML to JSON and simply address to the required value:
import xmltodict
with open('file.xml', 'r') as f:
data = xmltodict.parse(f.read())
changed_by = data['StationList']['Station']['ChangeHistory']['com:ChangedBy']
Output:
spascos

Try lxml:
#!/usr/bin/env python3
from lxml import etree
ns = {"com": "http://nationalrail.co.uk/xml/common"}
with open("so.xml") as f:
tree = etree.parse(f)
for t in tree.xpath("//com:ChangedBy/text()", namespaces=ns):
print(t)
Output:
spascos

You can use Beautifulsoup which is an html and xml parser
from bs4 import BeautifulSoup
fd = open(rootfilepath + "NRE_Station_Dataset_2019_raw.xml")
soup = BeautifulSoup(fd,'lxml-xml')
for i in soup.findAll('ChangeHistory'):
print(i.ChangedBy.text)

LXML add an element into root

Im trying to take two elements from one file (file1.xml), and write them onto the end of another file (file2.xml). I am able to get them to print out, but am stuck trying to write them onto file2.xml! Help !
filename = "file1.xml"
appendtoxml = "file2.xml"
output_file = appendtoxml.replace('.xml', '') + "_editedbyed.xml"
parser = etree.XMLParser(remove_blank_text=True)
tree = etree.parse(filename, parser)
etree.tostring(tree)
root = tree.getroot()
a = root.findall(".//Device")
b = root.findall(".//Speaker")
for r in a:
print etree.tostring(r)
for e in b:
print etree.tostring(e)
NewSub = etree.SubElement (root, "Audio(just writes audio..")
print NewSub
I want the results of a, b to be added onto the end of outputfile.xml in the root.

Parse both the input file and the file you wish to append to.
Use root.append(elt) to append Element, elt, to root.
Then use tree.write to write the new tree to a file (e.g. appendtoxml):
Note: The links above point to documentation for xml.etree from the standard
library. Since lxml's API tries to be compatible with the standard library's
xml.etree, the standard library documentation applies to lxml as well (at
least for these methods). See http://lxml.de/api.html for information on where
the APIs differ.
import lxml.etree as ET
filename = "file1.xml"
appendtoxml = "file2.xml"
output_file = appendtoxml.replace('.xml', '') + "_editedbyed.xml"
parser = ET.XMLParser(remove_blank_text=True)
tree = ET.parse(filename, parser)
root = tree.getroot()
out_tree = ET.parse(appendtoxml, parser)
out_root = out_tree.getroot()
for path in [".//Device", ".//Speaker"]:
for elt in root.findall(path):
out_root.append(elt)
out_tree.write(output_file, pretty_print=True)
If file1.xml contains
<?xml version="1.0"?>
<root>
<Speaker>boozhoo</Speaker>
<Device>waaboo</Device>
<Speaker>anin</Speaker>
<Device>gigiwishimowin</Device>
</root>
and file2.xml contains
<?xml version="1.0"?>
<root>
<Speaker>jubal</Speaker>
<Device>crane</Device>
</root>
then file2_editedbyed.xml will contain
<root>
<Speaker>jubal</Speaker>
<Device>crane</Device>
<Device>waaboo</Device>
<Device>gigiwishimowin</Device>
<Speaker>boozhoo</Speaker>
<Speaker>anin</Speaker>
</root>

How to change node value using lxml [duplicate]

I want to update xml file with new information by using lxml library.
For example, I have this code:
>>> from lxml import etree
>>>
>>> tree = etree.parse('books.xml')
where 'books.xml' file, has this content: http://www.w3schools.com/dom/books.xml
I want to update this file with new book:
>>> new_entry = etree.fromstring('''<book category="web" cover="paperback">
... <title lang="en">Learning XML 2</title>
... <author>Erik Ray</author>
... <year>2006</year>
... <price>49.95</price>
... </book>''')
My question is, how can I update tree element tree with new_entry tree and save the file.

Here you go, get the root of the tree, append your new element, save the tree as a string to a file:
from lxml import etree
tree = etree.parse('books.xml')
new_entry = etree.fromstring('''<book category="web" cover="paperback">
<title lang="en">Learning XML 2</title>
<author>Erik Ray</author>
<year>2006</year>
<price>49.95</price>
</book>''')
root = tree.getroot()
root.append(new_entry)
f = open('books-mod.xml', 'wb')
f.write(etree.tostring(root, pretty_print=True))
f.close()

I don't have enough reputation to comment, therefore I'll write an answer...
The most simple change make the code of Guillaume work is to change the line
f = open('books-mod.xml', 'w')
to
f = open('books-mod.xml', 'wb')