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The reduced function in Python takes in a function and a list as arguments and the function is called.

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With a lambda function like this and a replicator operation is performed or what D pairs of the list.

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So as per the lambda expression the argument is X and Y denote the element that the 0 it and the first

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index and the expression as per the expression.

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We need to add these elements at the 0 8 and the first index.

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So as a first step we apply the function on these two elements and an intermediate result is stored.

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So two plus three is five and in the next step the same function is applied on the intermediate result.

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And the element at the second index and the intermediate result is again stored.

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So this time five plus four is nine and this intermediate results stored again and in the third step.

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The function is applied on the intermediate result 9 and the element at the index number three and the

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intermediate result is stored again.

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And this process continues then no more elements are left in the list and the final result is returned.

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And remember that the function reduce stores the intermediate result and only to return to the final

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summation value.

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The reduced function is not commonly used in Python so it was removed from the building functions and

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python but it is still available in the function tools.

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Module in order to use the reduced function we have to import the function tools.

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This line in the cell that you see is used to import the reduced function from func tools import reduce

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now coming to what example I have defined a list L1 and using the reduced function.

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I want to calculate the sum of all the elements in this list.

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So I'm going to use a lambda function to calculate the sum of the elements and the arguments pass to

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the reduced function.

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The lambda function and then the list.

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List 1.

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So let's execute this one to execute this.

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You get the sum of all of these elements in the list

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and another example that we want to calculate.

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The element would be with the maximum value in this list.

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List too.

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So using the function that you use and then the lambda function I have past two arguments x and y x

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and y denote the elements in the list.

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So and in the expression we have a condition that in X and Y are compared and if x is greater than y

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the element x is written and the element Y is written and this expression is used to return the maximum

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value in the list.

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So let's execute this.

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And here we have the output.

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Now let's talk about the filter function.

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The filter function takes in a function and a list as the arguments and it applies this function on

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each of the elements in the list and the function.

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This particular function checks if the condition is true for each element in the list.

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Only if it is true if the condition turns out to be true only then the element is included in the output

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list.

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So let's see an example to understand the filter function.

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So here we have a filter function which includes a lambda function the lambda function checks if each

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element in the list is divisible by 2 or not.

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If the remainder is 0 or not and when we execute this the code in the cell we get an object.

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And if you want to create a list then you can parse this object to the list constructor and then execute

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and you have the elements which are divisible by two so here we have a map function that includes a

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lambda function and then and I a bill that is a list so the lambda function takes the argument X which

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indicate each element in the list and the expression here checks of each element is either greater or

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less than zero.

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If it is greater than zero then the function returns the Boolean value true.

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Is it returns false if the value of the element is greater than zero then it returns through.

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And if it is less than zero it returns false.

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And this condition is checked for all the elements in the list.

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So let's execute this code in the Jupiter notebook.