Class Objects Provide Default Behavior

When we run a class statement, we get a class object. Here’s a rundown of the main properties of Python classes:

 

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  • The class statement creates a class object and assigns it a name. Just like the function def statement, the Python class statement is an executable statement. When reached and run, it generates a new class object and assigns it to the name in the class header. Also, like defs, class statements typically run when the files they are coded in are first imported.
  • Assignments inside class statements make class attributes. Just like in module files, top-level assignments within a class statement (not nested in a def) generate attributes in a class object. Technically, the class statement scope morphs into the attribute namespace of the class object, just like a module’s global scope. After running a class statement, class attributes are accessed by name qualification: object.name.
  • Class attributes provide object state and behavior. Attributes of a class object record state information and behavior to be shared by all instances created from the class; function def statements nested inside a class generate methods, which process instances.