Functions and Modules

Define and Call a Function:

def make_shirt(size = "L", slogan = ""):                     # two params. One has a default value, other is optional
   """Generate a T-shirt order with size and slogan """      # for documentation of function purpose
   print(f"\nYou ordered a T-shirt saying '{slogan}' in size {size}.\n")

make_shirt()                                                 # call with defaults
make_shirt("M")                                              # call with size only
make_shirt(slogan = "I Love Python")                         # call with slogan only (must specify param name)
make_shirt(size = "S", slogan = "I Love Python")             # call with both size and slogan

Return a Dictionary from a Function:

def person(first_name, last_name, age = None):               # age is optional
    """Return names as dictionary"""
    person = {'first_name': first_name,                      # create the dictionary
         'last_name': last_name}
    if age:                                                  # manage optional age
         person['age'] = age
    return person                                            # return dictionary

writer = person('Thomas', 'Pynchon', 84)                     # call function
print(writer)                                                # print returned dictionary

def publish(submissions, published):
    """ Loop through submissions and move to published """
    while submissions:
        article = submissions.pop()
        print(f"Publishing submission: {article}")
        published.append(article)
        show_publications(published)
def show_publications(published)
    """ List published articles """
    print("The following articles are published:")
    for article in published:
        print(article)

submissions = [
    'Beginning Python',
    'Intermediate Python',
    'Advanced Python',
    ]
published = []

publish(submissions, published)

Pass an Arbitrary Number of Arguments

def make_pizza(*toppings):
    """Print list of toppings """
    print(toppings)
make_pizza('mushrooms', 'ham', 'oregano', 'extra cheese')