#  arbitrary numbers of arguments.

def add(*nums):  # * packing: convert/pack a number of values into a list
	return sum(nums)
    
print("""
def add(*args):
	return sum(args)
""")

print(f"add(): {add()}")
print(f"add(1,2,3,4,5): {add(1,2,3,4,5)}")
#   nums <- [1,2,3,4,5]
print(f"add(10,2,3,4,5,6,7): {add(10,2,3,4,5,6,7)}")

def multiplied_sum(*numbers, multiplier=1):
    total_sum = sum(numbers)
    return total_sum * multiplier

print("""
def multiplied_sum(*numbers, multiplier=1):
    total_sum = sum(numbers)
    return total_sum * multiplier
""")
print(f"multiplied_sum(1,2,3,4,multiplier=5): {multiplied_sum(1,2,3,4,multiplier=5)}")
print(f"multiplied_sum(1,2,3,4,5): {multiplied_sum(1,2,3,4,5)}")
print(f"multiplied_sum(1,2,3,4,6,7,8,9,10,0, multiplier=5): {multiplied_sum(1,2,3,4,6,7,8,9,10,0, multiplier=5)}")


def area(*, width, length):
    #   After *, only named arguments.
    return width * length
print("""
def area(*, width, length):
    return width * length
""")
    
print(f"area(width=2,length=3): {area(width=2,length=3)}")
print(
"""
print(f"area(2,3): {area(2,3)}")
TypeError: area() takes 0 positional arguments but 2 were given
"""
)
#   print(f"area(2,3): {area(2,3)}")

def area_with_weight(width, length, *, weight=1):
    #   After *, only named arguments.
    return width * length * weight
print("""
def area_with_weight(width, length, *, weight=1):
    #   After *, only named arguments.
    return width * length * weight
""")
print(f"area_with_weight(2,3): {area_with_weight(2,3)}")
print(f"area_with_weight(2,3,weight=2): {area_with_weight(2,3,weight=2)}")
print(f"area_with_weight(2,3,2): {area_with_weight(2,3,2)}")