Quick function to report materials present in an ISOXML file

import sys

from xml.etree import ElementTree as ET

def parse_isoxml(isoxml_file):

    tree = ET.parse(isoxml_file)

    root = tree.getroot()

    out_str = ""

    # find all "Isotope" elements

    isotopes = list(root.iter('Isotope'))

    out_str += f'Found {len(isotopes)} isotopes in the ISOXML:\n'

    for isotope in isotopes:

        out_str += f"\t{isotope.attrib['Name']}\n"

    return out_str

if __name__ == '__main__':

    print(f'Parsing XML file {sys.argv[1]}...')

    print(parse_isoxml(sys.argv[1]))