input: Write a function that takes any number of integer arguments and returns their sum. The function should collect the input values using variable-length argument syntax and iterate over them to calculate the total sum, which should then be returned. If no arguments are provided, the function should return 0.
  assert sum_ints()==0
  assert sum_ints(3, 5, 7)==15
  assert sum_ints(10, 20, 30, 40)==100
  assert sum_ints(-1, 5, -3, 2)==3
  assert sum_ints(-5, -3, -1)==-9
output: def sum_ints(*args):
      return sum(args)