Page 219 - Robotics and AI class 10
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The extend() Function
            The extend() function is used to append multiple values at a time in a list. The syntax of the extend() function is:
               list.extend(iterable value)
            where iterable value can be a list. Examples are:

                                     Commands                                     Output
                      n=[1,2,3,4]                               [1, 2, 3, 4, 5]

                      m=[5]
                      n.extend(m)
                      print(n)

                      pets = ['cat', 'dog', 'rabbit']           ['cat', 'dog', 'rabbit', 'tiger', 'lion']
                      wild=['tiger', 'lion']
                      pets.extend(wild)
                      print(pets)


            Some other Functions Used with List
            There are some other functions also available to use with the list which are as follows:
               • sort(): This function sorts the list in ascending or descending order. This is done "in the list itself" and works for
              the list with values of the same data types. For example,

                       city=["Delhi", "Mumbai", "Kolkata", "Chennai"]
                     city.sort() #sorts the list by default in ascending order

                       print(city)
               Output: ["Chennai", "Delhi", "Kolkata", "Mumbai"]

                    city.sort(reverse=True)#sorts the list descending order
               Output: ["Mumbai", "Kolkata", "Delhi", "Chennai"]


            Searching a value in a list
            Example 1
            Searching a specific value and displaying its number of occurrences in a list.

            A=[10,23,45,10,12,45,10,56]
            s=int(input("enter value you want to search :"))
            count=0

            for i in A:
                if i==s:
                    count+=1
            print(s," occurs ",count," times")
            Example 2
            Input a value and search whether it exists in a list or not. If it exists then display its index number.

            flowers=["Rose","Lily","Lotus","Sunflower"]

            s=input("Input a name of a flower :")

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