python简单的列表冒泡排序和反转列表

a=[3,4,6,2,1]
print a
def sortAndAddNew(a):
    b=[]
    l=len(a)
    for i in range(l):
        j=i
        for j in range(l):
            if (a[i]>a[j]):
                a[i],a[j]=a[j],a[i]

    for k in range(len(a)):
        b.append(a[k])
    return b

b=sortAndAddNew(a)
print b
print list(reversed(b))a=[3,4,6,2,1]
print a
def sortAndAddNew(a):