5200.8.5 可选参数

Making an Argument Optional

可以使用默认为空的参数，放在最后一个，作为可选择的参数。

def get_formatted_name(first_name, last_name, middle_name=''):
    """Return a full name, neatly formatted."""
    if middle_name:
        full_name = f"{first_name} {middle_name} {last_name}"
    else:
        full_name = f"{first_name} {last_name}"
    return full_name.title()
 
musician = get_formatted_name('jimi', 'hendrix')
print(musician)
 
musician = get_formatted_name('john', 'hooker', 'lee')
print(musician)