How can I create a dictioary with certain specific behaviour of values
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Suppose I have a list such as


    l1 = [['b', (1, 1)], ['b', (1, 2)], ['b', (1, 3)], ['a', (1, 5)], ['b', (2, 1)], ['b',(3, 1)]]

and another list 

    l2 = ['A','B','C']

How can I create a dictionary into this format:

    dct = {'A': len(sublist1), 'B': len(sublist2), 'C' : len(sublist3)} where,
    
    sublist1 = [['b', (1, 1)], ['b', (1, 2)], ['b', (1, 3)], ['a', (1, 5)]]
    sublist2 = [['b', (2, 1)]]
    sublist3 = [['b',(3, 1)]]
    
    
