why the syntex for function in python us def code example

Example 1: how to make a function in python

def test_function(argument1,argument2,argument3) :
  # Do something with the code, and the arguments.
  print(argument1)
  print(argument2)
  print(argument3)
  
# Calling the function.

test_function('Hello','World','!')

# Output
'''
Hello
World
!
'''

Example 2: what does * mean in python in functions

>>> numbers = [2, 1, 3, 4, 7]
>>> more_numbers = [*numbers, 11, 18]
>>> print(*more_numbers, sep=', ')
2, 1, 3, 4, 7, 11, 18