First syntax is python stuff.
In general you can pass variable inputs in a python function. This is enabled by setting a starred variable.
def dummy(x):

This function will accept a single input
def dummy(*x)

This function will accept any amount of inputs.
This start is used in that case to indicate variable amount of inputs, in the rest of cases it is used to unroll an iterable.
def dummy_star(*args):
    print(args)


def dummy(args):
    print(args)

dummy(7)

dummy_star(7,8)
# dummy(7,8) # Throws error as only a single input is allowed

list_of_inputs = [7,8,9]

dummy_star(*list_of_inputs,*list_of_inputs)
print('here you are unrolling list of inputs twice,thats why args is a tuple of ints')
dummy_star(list_of_inputs,list_of_inputs)
print('here you arent unrolling list of inputs twice,thats why args is a tuple of lists')

import torch
list_tensors = torch.rand(2,1)
dummy_star(*list_tensors,*list_tensors)
dummy_star(list_tensors,list_tensors)

Simply if you star a tensor you will iterate over dim 0 and will send each tensor in dim 0 as an input tensor
Btw: https://www.geeksforgeeks.org/args-kwargs-python/ 1