Rounding numbers in Python is quite common. There might be a situation where values must only be rounded to 3 decimals or some arbitrary number. Using the built-in function round() is handy but ...

Return number rounded to ndigits precision after the decimal point. If ndigits is omitted or is None, it returns the nearest integer to its input. This works incorrectly in the case of np.float64, ...

I’m 99.00001% sure that most programmers don’t understand just how cursed using floating point numbers is, when dynamic range isn’t needed.