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"""Unpacking Argument Lists

@see: https://docs.python.org/3/tutorial/controlflow.html#unpacking-argument-lists

Unpacking arguments may be executed via * and ** operators. See below for further details.

"""

def test_function_unpacking_arguments():

"""Unpacking Argument Lists"""

# The situation may occur when the arguments are already in a list or tuple but need to be

# unpacked for a function call requiring separate positional arguments. For instance, the

# built-in range() function expects separate start and stop arguments. If they are not

# available separately, write the function call with the *-operator to unpack the arguments out

# of a list or tuple:

# Normal call with separate arguments:

assert list(range(3, 6)) == [3, 4, 5]

# Call with arguments unpacked from a list.

arguments_list = [3, 6]

assert list(range(*arguments_list)) == [3, 4, 5]

# In the same fashion, dictionaries can deliver keyword arguments with the **-operator:

def function_that_receives_names_arguments(first_word, second_word):

return first_word + ', ' + second_word + '!'

arguments_dictionary = {'first_word': 'Hello', 'second_word': 'World'}

assert function_that_receives_names_arguments(**arguments_dictionary) == 'Hello, World!'