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.

The memory of a computer is a space where data is stored temporarily while the program is running. Values defined as variables are stored in memory, and Python accesses these values by referencing the memory address of the variable.

The is operator, which verifies if the objects being compared are the same, differs from the == operator.

While the == operator compares whether the values of two objects are equal, the is operator compares if the two objects are exactly the same object.

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, variables x and y have identical values but are distinct variables, thus stored in different memory addresses.

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 way, even if the values of two items are the same, == may return True, while is may return False.

It is advisable to use == for simple value comparisons and is when you need to strictly verify if two objects are completely identical.