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3.  All the keys in a dictionary must be of the same type.                                __________
                4.  A key in a dictionary can not be a mutable data type.                                 __________

                5.  If d is a dictionary, d[0] will yield its first key.                                  __________
                6.   If subjects = {'Sanskrit': 78, 'English': 185, 'Maths': 88,
                   'Hindi': 90} is a dictionary, subjects[0] will yield an error because a dict object
                   is not subscriptable.                                                                  __________
                7.  If d is a dictionary, d.keys()[0] will yield its first key.                           __________

            C. Fill in the blanks.
               1.  The expression print(len({1: 2, 2: 3, 1:2})) yields ____________.
               2.  Consider a dictionary:
                 myDict = {1:{2}, 2: {3:  5}}
                 The expression 3 in myDict yields ____________.
               3.  While working in IDLE environment, a dictionary rollnoMarks  of key value pairs rollNo:  marks has just been
                  created:
                 >>> rollnoMarks = {1:60,2:25,3:90,4:32,5:12,6:78}
                  The function call ____________ will yield the marks for the candidate with rollNo 4 and remove the pair 4:32  from
                  rollnoMarks.
               4.  Consider  the  dictionary  given  in  Ques  3.  The  expression  print(sorted(rollnoMarks.values()))  yields
                  ____________.

               5.  Consider a dictionary having the student details as follows:
                 studentDetails = {'Name':'Varun','Roll No': 5,'Marks':90}
                  The expression print(studentDetails.get('Roll No')) yields ____________.
               6.  Consider the same dictionary given in Ques. 5, the expression print(studentDetails.get('Roll Number'))
                  yields ____________.
            D.  Answer the following questions:
               1.  What will be the output produced on the execution of the following code snippet?
                 d1  = {1:2, 3:4}
                 d2  = {3:4, 1:2}
                 print(d1 == d2)
             Ans.  True
               2.  What will be the output produced on the execution of the following code snippet?
                 d1  = {1:2, 3:4}
                 d2  = {1:2, 3:4}
                 print(d1 is d2)
             Ans.  False
               3.  What will be the output produced on the execution of the following code snippet?
                 myDict = {}
                 val = 0
                 d = myDict.fromkeys([1,2,3,4],'val')
                 print(d)
             Ans.  {1: 'val', 2: 'val', 3: 'val', 4: 'val'}







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