• 第一题

def normalize(name):
    return str.capitalize(str.lower(name))

• 第二题

def prod(L):
    return reduce(lambda x, y: x * y , L)

• 第三题

def str2float(s):
    def char2num(c):
        return {'0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6, '7': 7, '8': 8, '9': 9}[c]
    def str2num(s):
        return reduce(lambda x, y : x * 10 + y, map(char2num, s))
    dot = s.find('.')
    return  str2num(s[:dot-1]) + str2num(s[dot+1:])/10** (len(s) - dot - 1)