When to Use \'is\' Keyword for String Equality in Python?

Understanding the Implementation of the 'is' Keyword in Python for String Equality

The 'is' keyword allows for identity testing in Python, a crucial concept for understanding its behavior. Despite its frequent use in string equality comparisons, its implementation differs from the methods __is__() and __eq__().

When comparing strings with 'is', the focus is on whether they reside at the same memory location. In Python, strings are typically stored in distinct memory addresses, unless they are interned. This process, known as interning, makes identical strings point to the same memory location, resulting in 'True' in 'is' comparisons.

However, overloading or manipulating 'is' for strings is strongly discouraged unless you fully understand the implications of interning. This is because 'is' tests for identity, not equality. For instance, '("a" 100) is ("a" 100)' returns 'False' because Python often allocates separate memory locations for each string.

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