Step 3: Operator Overloading

At this point, we have a fairly full-featured class that generates and initializes instances, along with two new bits of behavior for processing instances (in the form of methods). So far, so good.

As it stands, though, testing is still a bit less convenient than it needs to be—to trace our objects, we have to manually fetch and print individual attributes (e.g., bob.name, sue.pay). It would be nice if displaying an instance all at once actually gave us some useful information. Unfortunately, the default display format for an instance object isn’t very good—it displays the object’s class name, and its address in memory (which is essentially useless in Python, except as a unique identifier).

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To see this, change the last line in the script to print(sue) so it displays the object as a whole. Here’s what you’ll get (the output says that sue is an “object” in 3.0 and an “instance” in 2.6):

Bob Smith 0
Sue Jones 100000
Smith Jones
<__main__.Person object at 0x02614430>