python 中的多个方括号

Multiple square brackets in python

    def startpop(pop,job):
       i = 0 
       L = [[[(random.uniform(1,0))]]] 
       while i < pop:
          k = 0 
          if len(L) <= i:
          L.append([[random.uniform(1,0)]])

我正在尝试理解这段代码。三个方括号是什么意思?

是否只是一个list in a list中的list:

[
    [
       [
           (random.uniform(1,0))
       ]
    ]
 ]

>>> test = [[[1,2]]]
>>> print test[0]
[[1,2]]
>>> print test[0][0]
[1,2]
>>> print test[0][0][0]
1