python中怎么实现星星排列

def stars1(n):

for i in range(1,n+1):

str = "*"*i

print str

if __name__ ==  "__main__":

stars1(5)

def stars2(n):

for i in range(1,n+1):

str = '*'*(n+1-i)

print str

if __name__ ==  "__main__":

stars2(5)

def stars3(n):

for i in range(1,n+1):

str = ' ' * (n-i) + '*' * i

print str

if __name__ ==  "__main__":

stars3(5)

def stars4(n):

for i in range(1,1+n):#total n line(s)

str = ' '*(i-1) + '*'*(n+1-i)

print str

if __name__ ==  "__main__":

stars4(5)

def stars5(n):

    RANGE1 = [2*i+1 for i in range(n)]

    RANGE2 = [2*i+1 for i in range(n)[::-1]][1:]

    RANGE = RANGE1 + RANGE2

    RANGE_1 = [i for i in range(n)[::-1]]

    RANGE_2 = [i for i in range(n)[1:]]

    RANGE_12 = RANGE_1 + RANGE_2

    for i in range(len(RANGE)):

        print ' '*RANGE_12[i] + '*'*RANGE[i]

if __name__ ==  "__main__":

stars5(5)

def star6(n):

    a = [i*2+1 for i in range(n)[::-1]]

    b = [i*2+1 for i in range(n)][1:]

    aa = a + b

    d = [i for i in range(n)]

    e = [i for i in range(n)[::-1]][1:]

    dd = d + e

    for j in range(len(dd)):

        print ' '*dd[j] + '*'*aa[j]  

if __name__ == "__main__":

    star6(5)