def my_function() -> None:

"""

No argument, No Returns function.

>>> my_function()

hi

"""

print("hi")

def add(a: int, b: int) -> int:

"""

Add of a and b.

>>> add(3, 3)

6

>>> add(3, -3)

0

>>> add(99, 1)

100

"""

return a + b

def add_more(*args):

"""

Arbitrary Arguments

>>> add_more(1, 2, 3)

6

"""

return sum(args)

def calculate(a: int, operator: str, b: int) -> int:

"""

Simple calculator.

>>> calculate(a = 3, operator = "+", b = 4)

7

>>> calculate(a = 3, operator = "-", b = 4)

-1

>>> calculate(a = 3, operator = "*", b = 4)

12

>>> calculate(a = 3, operator = "/", b = 4)

0

>>> calculate(a = 3, operator = "!", b = 4)

Traceback (most recent call last):

...

ValueError: Invalid operator

"""

if operator == "+":

return a + b

elif operator == "-":

return a - b

elif operator == "*":

return a * b

elif operator == "/":

return a // b

else:

raise ValueError("Invalid operator")

def intro(**kwargs):

"""

>>> intro(name="Python", age = 29)

key=name, value=Python

key=age, value=29

"""

for (

key,

value,

) in kwargs.items():

print(f"key={key}, value={value}")

def print_number(number: int = 5) -> int:

"""

Default parameter.

>>> print_number(100)

100

>>> print_number()

5

"""

print(number)

def get_max(array):

"""

Pass list as parameter.

>>> get_max([1, 3, 5, 7, 9])

9

"""

max_value = array[0]

for item in array:

if item > max_value:

max_value = item

return max_value

def pass_function():

"""

>>> pass_function()

"""

pass # do anything.

def factorial(n: int) -> int:

"""

Recursion function.

>>> factorial(0)

1

>>> factorial(1)

1

>>> factorial(5)

120

>>> factorial(6)

720

"""

return 1 if n == 0 or n == 1 else n * factorial(n - 1)

if __name__ == "__main__":

from doctest import testmod

testmod()