sets and maps the provided implementation in sect helps to demonstrate the similarities between the implementation of the hashset class and the hashmap classor between the set and dict classes in python the two types of data structures are both implemented using hashing both rely heavily on ( membership test while understanding how the hashmap class is implemented is importantmost programming languages include some sort of hash map in their library of built-in typesas does python it is important to understand the complexity of the methods on hash mapbut just as important is understanding when to use hash map and how it can be used read on to see how you can use hash map in code you write to make it more efficient memoization memoization is an interesting programming technique that can be employed when you write functions that may get called more than once with the same arguments the idea behind memoization is to do the work of computing value in function once thenwe make note to ourselves so when the function is called with the same arguments againwe return the value we just computed again this avoids going to the work of computing the value all over again powerful example of this is the recursive fibonacci function the fibonacci sequence is defined as follows fib( fib( fib(nfib( - fib( - this sequence can be computed recursively by writing python function as follows def fib( )if = return if = return return fib( - fib( - howeverwe would never want to use this function for anything but simple demonstration of small fibonacci number the function cannot be used to computing something as big as fib( even running the function with an argument of will take very long time on even the fastest computers consider what happens to compute fib( to do that fib( and fib( must first be computed then the two results can be added together to find fib( butto compute fib( the values fib( and fib( must be computed now we are computing fib( twice to compute fib( )but to compute fib( we must compute fib( and fib( butfib( must be computed to find fib( as well figure shows all the calls to fib to compute fib( this copy belongs to 'acha