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3: The Function Object
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Summary
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- Functions is Python are objects and can be used anywhere an object can
- You can pass a function as a parameter and return a function result
- Function parameters are passed by object reference, which means changes to parameters do not affect the variables used as arguments
- Function s can have attributes defined which have a lifetime beyond that oof the functions local variables
- Local variables exist only while the function is being executed, but attributes exist as long as the function object does
- Lambda expressions are lightweight ways of creating function objects. They simplify the syntax for passing function arguments
- Functions have variables which reference them rather than names
- Functions can refer to their own attributes in code
- A function object is an example of a callable