[Tutor] "*" operator to unpack argument from a list or tuple

[Manprit Singh]

Dear Sir,
In python documentation there is a very good example of * as unpacking
operator, as given below:
ls = [3, 6]
print(sum(range(*ls)))   returns 12 which is a right answer, placing *ls
inside range()  created a  sequence of numbers as given - 3, 4, 5 and their
sum is 12.

See here in this example there is only one iterable being unpacked inside a
function call . Can we unpack more than one iterable inside function call
using "*' ?

Let's assume an example to find addition of all the numbers inside a list,
tuple & set, using function
ls = [2, 3]
tu = (3, 6)
st = {9, 1}
The sum will be 24

The implementation is given below:
def sumno(*seq):
    sumno = 0
    for num in seq:
        sumno += num
    return sumno

ls = [2, 3]
tu = (3, 6)
st = {9, 1}
ans = sumno(*ls, *tu, *st)
print(ans) returns 24, which is the right answer.
If you can see, i have unpacked the list, tuple & set inside the function
call, and i am concluding that all the numbers present inside the list,
tuple and set will be received by formal parameter seq in the form of
tuple, and hence the function sumno will return the sum of all numbers .

I just need to know if i can unpack multiple iterables using * in function
call or
not  as done in the previous example ?

A second example to generate a pattern given below:

         1
       1 2 1
     1 2 3 2 1
   1 2 3 4 3 2 1
 1 2 3 4 5 4 3 2 1

For the above pattern, if i write code as given below, is it correct instead

of that multiple for loop version conventional example taught in schools.


num = 5
for row in range(num):
    print("  "*(num-row-1), *range(1, row+2), *range(row, 0, -1))

Need your comments

Regards
Manprit Singh