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Let us now discuss about the concept immutability in Python.

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The ready builds.

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Act like pointers.

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No other than containers.

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So what do we mean by this say for example in A C programming language when we assign a likelihood to

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a variable the variable functions like a container that stores do well.

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So this assignment actually creates a block of memory space so that it can hold the value for that relevant.

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Now let's create another way to win B read B and assign oh where double E to variable b and this assignment

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again create a block of memory space so that the variable B can hold the value in coming to the Python

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language

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here in Python we create available C by assigning a value twenty so we have just just cause that in

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Python the variables act as point does to the memory locations the variable C will bind to a memory

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location which contains the value twenty now let's define another variable D which is now assigned to

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where the B C.

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So what does this mean in python in python.

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This assignment here means variable D point to the same value to which variable C is pointing to the

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variable C and variable D are pointing to the same memory location now as part of the program say we

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have assigned a new low to the variability C variable C now is equal to 40.

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So what does Python do now.

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Does it change the value in this particular memory location.

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No

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Python now makes the pointer variable C to point to the new value forty that is debatable D is still

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pointing to the old value twenty so the content in the memory location are not changed.

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The pointer is now pointing to a different memory location after the new assignment.

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So the content of the objects of immutable data types can not be changed after the ad created so this

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is about immutability of all these data types integer and flawed.

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So here I am taking a variable C which is binding to devalue 10.

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Now execute do code in this setting.

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By hitting shift and into these next

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I would like to check the memory location to which the pointer C is pointing to.

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So let's use the built in function idea and enter the object.

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See execute descent.

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So this is the memory location it is pointing to.

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Now let define another variable which has the same value as C..

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That means the DNC should point to the same memory location containing value 10.

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Now let's verify that again I D.

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Or D So or C and D are pointing to the same memory location.

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Now let's change the value or for the variability to 20 executed and then

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check for the memory location.

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So as you can see this memory location is different from what D pointing to so is D still pointing to

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10 or is it pointing to the new value that is 20.

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Let's check that

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so D is still pointing to the value 10 as you can see here.

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But C is now pointing to the value 20 which is in this particular memory location.

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So something is mutable only when we are able to change these values held in the memory location without

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changing the memory location itself.

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But another example then we have assigned a different value to the variable C it points to a different

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memory location containing the new value so this means building data types like integer flawed etc.

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are immutable will see a few more examples of strings as well.

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Shortly.