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Question

I am rather new to python. I have come across colleagues' code

def calc(lst):
    lst = [[some_var]]

What does it mean? I guess it's a double-dimensional array, but nothing more is coming to my mind

Thank you in advance

Answer 1

Variable points to a nested list, where length of outer as well as inner list is 1.

In [9]: lst = [[1]]

In [10]: len(lst)
Out[10]: 1

In [11]: len(lst[0])
Out[11]: 1

Appending list to an empty list,

In [12]: lst = []

In [13]: lst.append([1])

In [14]: lst
Out[14]: [[1]]

Answer 2

It depends on what data type some_var is holding. If some_var is a primitive data type, say integer, then lst is a list of list of an integer. But if some_var is a list itself, then lst is a list of list of list