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Python Object-Oriented Python Advanced Objects Math

How does 'other' instance know it will be treated as float?

In the magic method add(self, other), it returns float(self) + other (and int(self) + other ). How does 'other' instance know it is float? Don't we have to have float(self) + float(other)? I guess it automatically matches to the return type of self, but I know fully understand the mechanics of it.

2 Answers

Variables in Python follow the standard nomenclature of an alphanumeric name beginning in a letter or underscore. Variable names are case sensitive. Variables do not need to be declared and their datatypes are inferred from the assignment statement. So, Python use an aggressive type of inference. This means that python does not knows the type of variable until it runs the program, that's when it knows whether its int or float or string.