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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 parse_classified_by(content, normalize=True):
 """\ Returns the classificationist or ``None`` if the classificationist cannot be extracted. `content` The cable's content. """

    names = []
    m = _CLIST_CONTENT_PATTERN.search(content)
    if not m:
        return ()
    m = _CLSIST_PATTERN.search(m.group(1))
    if not m:
        return ()
    name = m.group(1).replace(u'\n', ' ')
    name = re.sub('[ ]+', ' ', name).rstrip(' -:').strip().replace(u'Y ee', u'Yee')
    if not name.upper().endswith(u'JR.'):
        name = name.rstrip(u'.')
    if normalize:
        name = name.replace(u'0', u'O').title()
        # Convert something like "Donald Duck, Iii" into "Donald Duck, III"
        names.append(re.sub(r'(Ii+)', lambda m: m.group(1).upper(), name))
    return names