Checking if Two Objects Are Identical with the 'is' Operator

In Python, everything is an object.

An object encompasses data and the associated actions (functions or methods) related to that data.

The is operator checks if two objects are the same object in memory.

Computer memory is a space where data is temporarily stored while a program is running. Variables are stored in memory, and Python accesses these values by referencing their memory addresses.

The is operator checks whether two variables refer to the exact same object in memory, unlike the == operator.

While the == operator checks if two objects have equal values, while the is operator checks if they are the same object in memory.

For example, to check if x and y are the same object, you would use x is y.

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x = [1, 2, 3]

y = [1, 2, 3]

print("x == y:", x == y)  # True, the values of x and y are equal

print("x is y:", x is y)  # False, x and y are different objects (different memory addresses)

In the example above, x and y have the same values but are stored at different memory addresses, so they are different objects.

Therefore, x is y returns False.

On the other hand, the == operator checks if the values of the two objects are the same, so x and y, which both have the value [1, 2, 3], return True for x == y.

In this case, even if two items have the same value, == may return True, while is may return False.

It is advisable to use == for simple value comparisons and is to strictly check if two objects are identical.