mutable v immutable objects

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Object Oriented Python example from a Well House Consultants training course
More on Object Oriented Python [link]

This example is described in the following article(s):
• Mutable v Immuatble objects in Python, and the implication - [link]

Source code: mute Module: Y106

# mutable v immutable objects

""" When you modify a mutable object, it changes in situ
but when you modify (or think you modify) an immutable object,
a fresh object is created. This means that when you pass an
immutable object to a function you cannot modify it in there
(it is, after all, immutable) and you will produce a local
copy within the function if you do. However, if you pass a
mutable object to a function and change it within, that change
will be reflected out in the calling code """

def one (first):
        first += 5
        return first

def two (second):
        second += [5]
        return second

f = 27
s = [27]

x = one(f)
y = two(s)

print(f)
print(s)

print(x,y)

""" Sample output

WomanWithCat:y106 grahamellis$ python2 mute
27
[27, 5]
(32, [27, 5])
WomanWithCat:y106 grahamellis$ python3 mute
27
[27, 5]
32 [27, 5]
WomanWithCat:y106 grahamellis$

"""

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