python - How to find the number of nested lists in a list?

Question

The function takes a list and returns an int depending on how many lists are in the list not including the list itself. (For the sake of simplicity we can assume everything is either an integer or a list.)

For example:

x=[1,2,[[[]]],[[]],3,4,[1,2,3,4,[[]] ] ]

count_list(x) # would return 8

I think using recursion would help but I am not sure how to implement it, this is what I have so far.

def count_list(a,count=None, i=None):

    if count==None and i==None:
        count=0
        i=0
    if i>len(a)
        return(count)
    if a[i]==list
       i+=1
       count+=1
       return(count_list(a[i][i],count))
    else:
        i+=1
        return(count_list(a[i]))

Answer 1

You can use a recursion function as following:

In [14]: def count(l):
    ...:     return sum(1 + count(i) for i in l if isinstance(i,list))
    ...: 

In [15]: 

In [15]: x=[1,2,[[[]]],[[]],3,4,[1,2,3,4,[[]] ] ]

In [16]: count(x)
Out[16]: 8