In Python, it’s possible to perform mathematical operations inside of string literals, using a feature called “f-strings”. F-strings, or “formatted string literals”, allow you to embed expressions inside string literals, which are evaluated at runtime. This allows you to mix variables, arithmetic expressions, and other computations into strings in a very readable and convenient way.

num_val = 42

print(f'{num_val % 2 = }') # num_val % 2 = 0

Here, the f-string '{num_val % 2 = }' is a string literal that contains an expression num_val % 2. The % operator is used to perform the modulo operation, which returns the remainder of the division of one number by another. In this case, num_val % 2 returns the remainder of the division of 42 by 2, which is 0.

When the f-string is evaluated, the expression num_val % 2 is calculated and its value is included in the output string. The result of the above code is the following:

num_val % 2 = 0

As you can see, f-strings allow you to easily include the results of arithmetic expressions in string literals. This can be especially useful when you need to display results from computations or debug information in your program, as it enables you to insert calculated values into text output in a readable and concise way.

It’s worth noting that f-strings can contain not just arithmetic expressions but any valid Python expression. For example, you can use them to include the results of function calls or to embed data structures like lists or dictionaries in strings.

In conclusion, f-strings are a powerful feature of Python that allow you to perform math operations inside of strings. They are a readable and convenient way to include calculated values into string output, and their versatility makes them a valuable tool in a variety of applications.