练习一

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

练习二

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

练习三

#拷贝的本页原有代码
def char2num(s):
    return {'0': 0, '1': 1, '2': 2, '3': 3, '4': 4, '5': 5, '6': 6, '7': 7, '8': 8, '9': 9}[s]

def str2float(s):
    a,b=s.split('.')
    num=reduce(lambda x,y:x*10+y,map(char2num,(a+b)))
    return num/(10**len(b))