Q.Program 7-5: Write a program using user defined function that accepts an integer and increments the value by 5. Also display the id of argument (before function call), id of parameter before increment and after increment.

Integers are immutable, so num = num + 5 inside the function creates a new object: the parameter's id equals the argument's id until the increment, then changes — and the caller's variable is untouched.

def incrValue(num):
    print("id of parameter before increment:", id(num))
    num = num + 5
    print("id of parameter after increment :", id(num))
    print("num after increment inside function:", num)

value = 10
print("id of argument before function call:", id(value))
incrValue(value)
print("value after the function call:", value)

Sample output (ids are memory addresses — the actual numbers differ per machine/run):

id of argument before function call: 9793280
id of parameter before increment: 9793280
id of parameter after increment : 9793440 …

The idea — pass by object reference. Python passes a reference to the object, not a copy. id() returns an object's identity (its memory address in CPython), so printing ids before and after the increment shows exactly when the parameter stops sharing the argument's object.

# Program 7-5: increment a value by 5 and observe the ids

def incrValue(num):
    print("id of parameter before increment:", id(num))
    num = num + 5                     # rebinds num to a NEW int object
    print("id of parameter after increment :", id(num))
    print("num after increment inside function:", num)

value = 10
print("id of argument before function call:", id(value))
incrValue(value)
print("value after the function call:", value)

Expected output — sample run (ids are memory addresses; the exact numbers will differ on your machine, but the pattern will not):

id of argument before function call: 9793280
id of parameter before increment: 9793280
id of parameter after increment : 9793440
num after increment inside function: 15
value after the function call: 10

Reading the run

1. id(value) and the parameter's id before the increment are identical — argument and parameter are two names for the one object 10. …