The values arrive as tuple.

examples/functions/sum.py
from __future__ import print_function

def mysum(*numbers):
    print(numbers)
    total = 0
    for s in numbers:
        total += s
    return total

print(mysum(1))
print(mysum(1, 2))
print(mysum(1, 1, 1))

x = [2, 3, 5, 6]
print(mysum(*x))

examples/functions/sum.py.out
(1,)
1
(1, 2)
3
(1, 1, 1)
3