Page 341 - Computer Science Class 11 With Functions
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Note that the list student includes three types of objects, namely, str, int, and list.
            Next, we define another heterogeneous list mixedList:

             >>> mixedList = [1, [2, 3], 'three', 4.0]
            Interestingly, the elements of a list may also be names of the functions. For instance, in the following statements, we
            first define two functions, namely, f1() and f2(). Subsequently, we create a list lst comprising the names f1
            and f2. Finally,  we invoke these two functions using elements at index 0 and 1 of the list lst.
             >>> def f1(n):
             ...     return n**2
             ...
             >>> def f2(n):
             ...     return n**3
             ...
             >>> functions = [f1, f2]
             >>> print('f1(5): ', functions[0](5))
                 f1(5):  25
             >>> print('f2(5): ', functions[1](5))
                 f2(5):  125
             >>>
            13.5 More Operations on Lists

            ●  Concatenation Operator + : The +  operator concatenates a pair of lists. The concatenated list comprises the
              elements of the first list on the left hand side of the + operator, followed by the elements of the second list on the
              right hand side of the + operator.
             >>> lst1 = ['Red', 'Green']
             >>> lst2 = ['Blue']
             >>> print('id(lst1): ', id(lst1))
                 id(lst1):  3237079561600
             >>> print('id(lst2): ', id(lst2))
                 id(lst2):  3237079384384
             >>> lst1 = lst1 + lst2
             >>> lst1
                 ['Red', 'Green', 'Blue']
             >>> print('id(lst1): ', id(lst1))
                 id(lst1):  3237079385664
            Note that the concatenation operator creates a new object for the concatenated list.

            We have seen above that the assignment
            lst1 = lst1 + lst2
            creates a new object which is assigned to lst1. However, the Python operator +=  updates the existing list lst1. For
            example,

             >>> lst1 = [10, 5, 20]
             >>> lst2 = [9, 7]
             >>> print('id(lst1): ', id(lst1))
                 id(lst1):  3237079560384
             >>> lst1 += lst2
             >>> lst1
                 [10, 5, 20, 9, 7]
             >>> print('id(lst1): ', id(lst1))
                 id(lst1):  3237079560384
            ●  Multiplication Operator *: The * operator concatenates a list the specified number of times and yields a new list.
              For example,
             >>> lst = [ 4, 12, 9]
             >>> print('id(lst): ', id(lst))


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