Question: 
Write a function to count the number of sublists containing a particular element.


Model's Code:
def count_element_in_list(lst, elem):
    return sum(1 for sublist in lst if elem in sublist)



Sample Correct Code:
def count_element_in_list(list1, x): 
    ctr = 0
    for i in range(len(list1)): 
        if x in list1[i]: 
            ctr+= 1          
    return ctr


Asserts:
assert count_element_in_list([[1, 3], [5, 7], [1, 11], [1, 15, 7]],1)==3
assert count_element_in_list([['A', 'B'], ['A', 'C'], ['A', 'D', 'E'], ['B', 'C', 'D']],'A')==3
assert count_element_in_list([['A', 'B'], ['A', 'C'], ['A', 'D', 'E'], ['B', 'C', 'D']],'E')==1


Tests:
Test 1 of 3: PASS
Test 2 of 3: PASS
Test 3 of 3: PASS

Test 425 of 974: 310/425 (72.94117647058823%): success