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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_alleles():
 """Parses the IEDB MhcAlleleName XML file and returns a list of Allele namedtuple objects containing information about that each allele's HLA class and source organism. """

    result = []
    path = local_path()
    etree = xml.etree.ElementTree.parse(path)
    for allele in etree.iterfind("MhcAlleleName"):
        name_element = allele.find("DisplayedRestriction")
        mhc_class_element = allele.find("Class")
        # need at least a name and an HLA class
        if name_element is None or mhc_class_element is None:
            continue
        name = name_element.text

        synonyms = set([])
        for synonym_element in allele.iterfind("Synonyms"):
            for synonym in synonym_element.text.split(","):
                synonyms.add(synonym.strip())
        mhc_class = mhc_class_element.text
        organism_element = allele.find("Organsim")
        if organism_element is None:
            organism = None
        else:
            organism = organism_element.text

        locus_element = allele.find("Locus")

        if locus_element is None:
            locus = None
        else:
            locus = locus_element.text

        allele_object = Allele(
            name=name,
            mhc_class=mhc_class,
            locus=locus,
            organism=organism,
            synonyms=synonyms)
        result.append(allele_object)
    return result