Геродот

def solution(soup):
    arr = soup.find('ul',attrs={'id': 'pagehistory'}).find_all('li')
    res = {}
    for i in arr:
        s = i.find('span',attrs={'class': 'history-user'}).find('bdi').text
        res[s] = res.setdefault(s, 0)+1
    print(res)
    return max(res, key=res.get)