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can we search multiple pattern using etree findall() in xml?

For my case, I have to find few elements in the XML file and update their values using the text attribute. For that, I have to search xml element A, B and C. My project is using xml.etree and python language. Currently I am using:
self.get_root.findall(H/A/T)
self.get_root.findall(H/B/T)
self.get_root.findall(H/C/T)
The sample XML file:
<H><A><T>text-i-have-to-update</H></A></T>
<H><B><T>text-i-have-to-update</H></B></T>
<H><C><T>text-i-have-to-update</H></C></T>
As we can notice, only the middle element in the path is different. Is there a way to optimize the code using something like self.get_root.findall(H|(A,B,C)|T)? Any guidance in the right direction will do! Thanks!
I went through the similar question: XPath to select multiple tags but it didn't work for my case
Update: maybe regular expression inside the findall()?

The html in your question is malformed; assuming it's properly formatted (like below), try this:
import xml.etree.ElementTree as ET
data = """<root>
<H><A><T>text-i-have-to-update</T></A></H>
<H><B><T>text-i-have-to-update</T></B></H>
<H><C><T>text-i-have-to-update</T></C></H>
</root>"""
doc = ET.fromstring(data)
for item in doc.findall('.//H//T'):
item.text = "modified text"
print(ET.tostring(doc).decode())
Output:
<root>
<H><A><T>modified text</T></A></H>
<H><B><T>modified text</T></B></H>
<H><C><T>modified text</T></C></H>
</root>

Python XML Parser not Returning XML Elemements

I am trying to find a way to use Python to parse data from several .xml files that contain part numbers and descriptions for a system my team is working on. Here's what the files look like:
Note: Actual data sanitized for confidentiality reasons.
<DOCUMENT>
<config>
<lruname>NFS</lruname>
<swpn>123-A-456-7890</swpn>
<swname>00 NFS ABC DEFGHI XYZ JKL</swname>
<swver>Appid: abc-defghi-xyz PN: 123-A-456-7890</swver>
</config>
</DOCUMENT>
I'd like to pull the and datatypes from several of these files into .csv format. My initial thought was to try to parse these data types out into a dictionary using the built in xml.etree library, but for some reason it's not finding the elements:
import xml.etree.ElementTree as ET
data = '''
<DOCUMENT>
<config>
<lruname>NFS</lruname>
<swpn>123-A-456-7890</swpn>
<swname>00 NFS ABC DEFGHI XYZ JKL</swname>
<swver>Appid: abc-defghi-xyz PN: 123-A-456-7890</swver>
</config>
</DOCUMENT>
'''
tree = ET.fromstring(data)
PartNo = tree.find('swpn')
Desc = tree.find('swname')
print(PartNo)
The above code returns 'None' for some reason, but I would expect it to return the xml element I'm calling.

I think you're missing the config level in your XML hierarchy, you could do:
part_number = tree.find('config').find('swpn').text
part_desc = tree.find('config').find('swname').text
Alternately you can loop through all the elements if you don't want to have to know the structure and use conditionals to find the elements you care about with tree.iter.
for e in tree.iter():
if e.tag == 'sqpn':
part_number = e.text
if e.tag == 'swname':
part_desc = e.text

ElementTree and etree's find functionality searchers for direct children.
You can still use it by specifying the entire branch:
tree.find('config').find('swpn')
tree.find('config/swpn')
If you always want to look for swpn, but disregard the structure (e.g. you don't know if it's going to be a child of config), you might find it easier to use the xpath functionality in etree (and not in ElementTree):
tree = etree.fromstring(data)
tree.xpath('//swpn')
In this case, the // basically mean that you are looking for elements in tree, no matter where they are
If the xml files are small, and you don't care about performance, you can use minidom which IMHO is more convenient compared to lxml. In this case, your code could be something like this:
from xml.dom.minidom import parseString
xml = parseString(data)
PartNo = xml.getElementsByTagName('swpn')[0]
Desc = xml.getElementsByTagName('swname')[0]
print(PartNo.firstChild.nodeValue)

Trouble retrieving text from XML with ElementTree with tags

Right now I have some code which uses Biopython and NCBI's "Entrez" API to get XML strings from Pubmed Central. I'm trying to parse the XML with ElementTree to just have the text from the page. Although I have BeautifulSoup code that does exactly this when I scrape the lxml data from the site itself, I'm switching to the NCBI API since scrapers are apparently a no-no. But now with the XML from the NCBI API, I'm finding ElementTree extremely unintuitive and could really use some help getting it to work. Of course I've looked at other posts, but most of these deal with namespaces and in my case, I just want to use the XML tags to grab information. Even the ElementTree documentation doesn't go into this (from what I can tell). Can anyone help me figure out the syntax to grab information within certain tags rather than within certain namespaces?
Here's an example. Note: I use Python 3.4
Small snippit of the XML:
<sec sec-type="materials|methods" id="s5">
<title>Materials and Methods</title>
<sec id="s5a">
<title>Overgo design</title>
<p>In order to screen the saltwater crocodile genomic BAC library described below, four overgo pairs (forward and reverse) were designed (<xref ref-type="table" rid="pone-0114631-t002">Table 2</xref>) using saltwater crocodile sequences of MHC class I and II from previous studies <xref rid="pone.0114631-Jaratlerdsiri1" ref-type="bibr">[40]</xref>, <xref rid="pone.0114631-Jaratlerdsiri3" ref-type="bibr">[42]</xref>. The overgos were designed using OligoSpawn software, with a GC content of 50–60% and 36 bp in length (8-bp overlapping) <xref rid="pone.0114631-Zheng1" ref-type="bibr">[77]</xref>. The specificity of the overgos was checked against vertebrate sequences using the basic local alignment search tool (BLAST; <ext-link ext-link-type="uri" xlink:href="http://www.ncbi.nlm.nih.gov/">http://www.ncbi.nlm.nih.gov/</ext-link>).</p>
<table-wrap id="pone-0114631-t002" orientation="portrait" position="float">
<object-id pub-id-type="doi">10.1371/journal.pone.0114631.t002</object-id>
<label>Table 2</label>
<caption>
<title>Four pairs of forward and reverse overgos used for BAC library screening of MHC-associated BACs.</title>
</caption>
<alternatives>
<graphic id="pone-0114631-t002-2" xlink:href="pone.0114631.t002"/>
<table frame="hsides" rules="groups">
<colgroup span="1">
<col align="left" span="1"/>
<col align="center" span="1"/>
</colgroup>
For my project, I want all of the text in the "p" tag (not just for this snippit of the XML, but for the entire XML string).
Now, I already know that I can make the whole XML string into an ElementTree Object
>>> import xml.etree.ElementTree as ET
>>> tree = ET.ElementTree(ET.fromstring(xml_string))
>>> root = ET.fromstring(xml_string)
Now if I try to get the text using the tag like this:
>>> text = root.find('p')
>>> print("".join(text.itertext()))
or
>>> text = root.get('p').text
I can't extract the text that I want. From what I've read, this is because I'm using the tag "p" as an argument rather than a namespace.
While I feel like it should be quite simple for me to get all the text in "p" tags within an XML file, I'm currently unable to do it. Please let me know what I'm missing and how I can fix this. Thanks!
--- EDIT ---
So now I know that I should be using this code to get everything in the 'p' tags:
>>> text = root.find('.//p')
>>> print("".join(text.itertext()))
Despite the fact that I'm using itertext(), it's only returning content from the first "p" tag and not looking at any other content. Does itertext() only iterate within a tag? Documentation seems to suggest it iterates across all tags as well, so I'm not sure why its only returning one line instead of all of the text under all of the "p" tags.
---- FINAL EDIT --
I figured out that itertext() only works within one tag and find() only returns the first item. In order to get the enitre text that I want I must use findall()
>>> all_text = root.findall('.//p')
>>> for texts in all_text:
print("".join(texts.itertext()))

root.get() is the wrong method, as it will retrieve an attribute of the root tag not a subtag.
root.find() is correct as it will find the first matching subtag (alternatively one can use root.findall() for all matching subtags).
If you want to find not only direct subtags but also indirect subtags (as in your example), the expression within root.find/root.findall has be to a subset of XPath (see https://docs.python.org/2/library/xml.etree.elementtree.html#xpath-support). In your case it is './/p':
text = root.find('.//p')
print("".join(text.itertext()))

Parsing XML data within tags using lxml in python

My question is regarding how to get information stored in a tag which allows for no closing tag. Here's the relevant xml:
<?xml version="1.0" encoding="UTF-8"?>
<uws:job>
<uws:results>
<uws:result id="2014-03-03T15:42:31:1337" xlink:href="http://www.cosmosim.org/query/index/stream/table/2014-03-03T15%3A42%3A31%3A1337/format/csv" xlink:type="simple"/>
</uws:results>
</uws:job>
I'm looking to extract the xlink:href url here. As you can see the uws:result tag requires no closing tag. Additionally, having the 'uws:' makes it a bit tricky to handle them when working in python. Here's what I've tried so far:
from lxml import etree
root = etree.fromstring(xmlresponse.content)
url = root.find('{*}results').text
Where xmlresponse.content is the xml data to be parsed. What this returns is
'\n '
which indicates that it's only finding the newline character, since what I'm really after is contained within a tag inside the results tag. Any ideas would be greatly appreciated.

You found the right node; you extracted the data incorrectly. Instead of
url = root.find('{*}results').text
you really want
url = root.find('{*}results').get('attribname', 'value_to_return_if_not_present')
or
url = root.find('{*}results').attrib['attribname']
(which will throw an exception if not present).
Because of the namespace on the attribute itself, you will probably need to use the {ns}attrib syntax to look it up too.
You can dump out the attrib dictionary and just copy the attribute name out too.
text is actually the space between elements, and is not normally used but is supported both for spacing (like etreeindent) and some special cases.

Targeting specific sub-elements when parsing XML with Python

I'm working on building a simple parser to handle a regular data feed at work. This post, XML to csv(-like) format , has been very helpful. I'm using a for loop like in the solution, to loop through all of the elements/subelements I need to target but I'm still a bit stuck.
For instance, my xml file is structured like so:
<root>
<product>
<identifier>12</identifier>
<identifier>ab</identifier>
<contributor>Alex</contributor>
<contributor>Steve</contributor>
</product>
<root>
I want to target only the second identifier, and only the first contributor. Any suggestions on how might I do that?
Cheers!

The other answer you pointed to has an example of how to turn all instances of a tag into a list. You could just loop through those and discard the ones you're not interested in.
However, there's a way to do this directly with XPath: the mini-language supports item indexes in brackets:
import xml.etree.ElementTree as etree
document = etree.parse(open("your.xml"))
secondIdentifier = document.find(".//product/identifier[2]")
firstContributor = document.find(".//product/contributor[1]")
print secondIdentifier, firstContributor
prints
'ab', 'Alex'
Note that in XPath, the first index is 1, not 0.
ElementTree's find and findall only support a subset of XPath, described here. Full XPath, described in brief on W3Schools and more fully in the W3C's normative document is available from lxml, a third-party package, but one that is widely available. With lxml, the example would look like this:
import lxml.etree as etree
document = etree.parse(open("your.xml"))
secondIdentifier = document.xpath(".//product/identifier[2]")[0]
firstContributor = document.xpath(".//product/contributor[1]")[0]
print secondIdentifier, firstContributor