Test Your Knowledge: Answers

 

 
  1. An if statement with multiple elif clauses is often the most straightforward way to code a multiway branch, though not necessarily the most concise. Dictionary indexing can often achieve the same result, especially if the dictionary contains callable functions coded with def statements or lambda expressions.
  2. In Python 2.5 and later, the expression form Y if X else Z returns Y if X is true, or Z otherwise; it’s the same as a four-line if statement. The and/or combination (((X and Y) or Z)) can work the same way, but it’s more obscure and requires that the Y part be true.
  3. Wrap up the statement in an open syntactic pair ((), [], or {}), and it can span as many lines as you like; the statement ends when Python sees the closing (right) half of the pair, and lines 2 and beyond of the statement can begin at any indentation level.
  4. True and False are just custom versions of the integers 1 and 0, respectively: they always stand for Boolean true and false values in Python. They’re available for use in truth tests and variable initialization and are printed for expression results at the interactive prompt.