60 lines
1.8 KiB
Markdown
60 lines
1.8 KiB
Markdown
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# CHAPTER 3 - FUNCTIONS
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> Q: 1. Why are functions advantageous to have in your programs?
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A: Avoid duplicating codes.
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> Q: 2. When does the code in a function execute: when the function is defined or when the function is called?
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A: called.
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> Q: 3. What statement creates a function?
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A: `def` statements.
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> Q: 4. What is the difference between a function and a function call?
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A: A function consists of the def statement and the code in its `def` clause.
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A function call is what moves the program execution into the function, and the function call evaluates to the function's return value.
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> Q: 5. How many global scopes are there in a Python program? How many local scopes?
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A: Just one global scope, and a local scope is created whenever a function is called.
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> Q: 6. What happens to variables in a local scope when the function call returns?
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A: destroyed.
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> Q: 7. What is a return value? Can a return value be part of an expression?
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A: return value is the result of a function call. Return value can be part of an expression.
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> Q: 8. If a function does not have a return statement, what is the return value of a call to that function?
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A: `None`.
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> Q: 9. How can you force a variable in a function to refer to the global variable?
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A: `global` statement.
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> Q: 10. What is the data type of None?
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A: `NoneType`
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> Q: 11. What does the import `areallyourpetsnamederic ` statement do?
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A: import a module named `areallyourpetsnamederic `.
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> Q: 12. If you had a function named bacon() in a module named spam, how would you call it after importing spam?
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A: `spam.bacon()`
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> Q: 13. How can you prevent a program from crashing when it gets an error?
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A: use `try...except...`
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> Q: 14. What goes in the try clause? What goes in the except clause?
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A: potential error goes in the `try` clause, then if the error happens, goes in the `except` clause.
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