mutable immutable [Python] function

# immutable

def func(x):

print("x", hex(id(x)), x)

x += 1

print("x", hex(id(x)), x)

def main():

a = 1

print("a", hex(id(a)), a)

func(a)

print("a", hex(id(a)), a)

if __name__ == '__main__':

main()

""" Output

a 0x67298070 1

x 0x67298070 1

x 0x67298090 2

a 0x67298070 1

"""

# mutable

def func(x):

print("x", hex(id(x)), x)

x.append(3)

print("x", hex(id(x)), x)

def main():

a = [1, 2]

print("a", hex(id(a)), a)

func(a)

print("a", hex(id(a)), a)

if __name__ == '__main__':

main()

""" Output

a 0x209691aa188 [1, 2]

x 0x209691aa188 [1, 2]

x 0x209691aa188 [1, 2, 3]

a 0x209691aa188 [1, 2, 3]

"""