python 删除/查找重复项

转自我的博客园：http://www.cnblogs.com/vickey-wu/p/6579653.html

l = [1,2,3,2,1]

# l = ['你','我','他','她','你']　　
for i in l:
    print("the %s has found %s" % (i, l.count(i)))          #find duplicate number
    # print("the %s has found %s" % (i, l.count(i)))　　　  #find duplicate string
#the method above would repeat count duplicate data ,so we need to remove duplicate first
print 'split line ----------------------------'
s = set(l)
for j in s:
    print("the %s has found %s" % (j, l.count(j)))      
    #find duplicate number    print("the %s has found %s" % (j, l.count(j)))      #find duplicate number