计算重复列表的频率-在列表列表中

我在python中有一个列表列表，我需要查找每个子列表出现了多少次.这是一个示例，

I have a list of lists in python and I need to find how many times each sub-list has occurred. Here is a sample,

from collections import Counter
list1 = [[ 1., 4., 2.5], [ 1., 2.66666667, 1.33333333], 
         [ 1., 2., 2.], [ 1., 2.66666667, 1.33333333], [ 1., 4., 2.5],
         [ 1., 2.66666667, 1.33333333]]   
c = Counter(x for x in iter(list1))
print c

如果列表中的元素是可哈希的(例如int)，则上面的代码将起作用，但是在这种情况下，它们是列表，并且会出现错误

I above code will work, if the elements of the list were hashable (say int), but in this case they are lists and I get an error

TypeError: unhashable type: 'list'

我该如何计算这些列表，以便得到类似的信息

How can I count these lists so I get something like

[ 1., 2.66666667, 1.33333333], 3
[ 1., 4., 2.5], 2
[ 1., 2., 2.], 1