How to put xml tree into separate python file?

Question

I use python and xml.etree.ElementTree for building a xml file. But only the base tree has more than 350 lines and I would like to put this in a seperate file. How do I do that?

My code:

import xml.etree.ElementTree as ET

***
mydata = ET.Element('root_data')
version = ET.SubElement(root_data, 'version')
date = ET.SubElement(root_data, 'date')
groups = ET.SubElement(root_data, 'groups')
group = ET.SubElement(groups, 'group')
templates = ET.SubElement(root_data, 'templates')
template = ET.SubElement(templates, 'template')
tpl_linked = ET.SubElement(template, 'template')
--- a lot more lines like this ---
***

So I would like to have the stuff between the *** in a separate file.

I tried to call it via a function, but that did not work because then the variables were not known in the main program.

Answer 1

xml.etree.ElementTree have a tree.write() function to file, see the documentation.

import xml.etree.ElementTree as ET

root_data = ET.Element('root_data') # corrected your code here
version = ET.SubElement(root_data, 'version')
date = ET.SubElement(root_data, 'date')
groups = ET.SubElement(root_data, 'groups')
group = ET.SubElement(groups, 'group')
templates = ET.SubElement(root_data, 'templates')
template = ET.SubElement(templates, 'template')
tpl_linked = ET.SubElement(template, 'template')

# For better format
ET.indent(root_data, space='  ')
ET.dump(root_data)

# Write the tree to file
tree = ET.ElementTree(root_data)
tree.write('output_file.xml', encoding='utf-8', xml_declaration=True)

Addition: Assume you have a file temp.py:

import xml.etree.ElementTree as ET


def xml_temp():
    root_data = ET.Element('root_data')
    version = ET.SubElement(root_data, 'version')
    date = ET.SubElement(root_data, 'date')
    groups = ET.SubElement(root_data, 'groups')
    group = ET.SubElement(groups, 'group')
    templates = ET.SubElement(root_data, 'templates')
    template = ET.SubElement(templates, 'template')
    tpl_linked = ET.SubElement(template, 'template')
    return root_data

if __name__ == '__main__':
    xml_temp()

This could be imported as other modules, read the modul documentation or packaging for more details. For example you have another python main file, e.g. xml_file.py:

import xml.etree.ElementTree as ET
from temp import xml_temp

root = xml_temp()
ET.indent(root, space='  ')
ET.dump(root)

Output:

<root_data>
  <version />
  <date />
  <groups>
    <group />
  </groups>
  <templates>
    <template>
      <template />
    </template>
  </templates>
</root_data>