Variable length argument list with * and **

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examples/advanced/varargs.py

def f(a, b=1, *args, **kwargs):
    print('a:     ', a)
    print('b:     ', b)
    print('args:  ', args)
    print('kwargs:', kwargs)
    return a + b

f(2, 3, 4, 5, c=6, d=7)
print()
f(2, c=5, d=6)
print()
f(10)

a:      2
b:      3
args:   (4, 5)
kwargs: {'c': 6, 'd': 7}

a:      2
b:      1
args:   ()
kwargs: {'c': 5, 'd': 6}

a:      10
b:      1
args:   ()
kwargs: {}