Write a function to find frequency count of list of lists.
def frequency_lists(list1):
    list1 = [item for sublist in list1 for item in sublist]
    dic_data = {}
    for num in list1:
        if num in dic_data.keys():
            dic_data[num] += 1
        else:
            key = num
            value = 1
            dic_data[key] = value
    return dic_data

<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a function to find frequency count of list of lists.
def frequency_lists(list1):
    list1 = [item for sublist in list1 for item in sublist]
    dic_data = {}
    for num in list1:
        if num in dic_data.keys():
            dic_data[num] += 1
        else:
            key = num
            value = 1
            dic_data[key] = value
    return dic_data
[/INST]assert frequency_lists([[1, 2, 3, 2], [4, 5, 6, 2], [7, 8, 9, 5]])=={1: 1, 2: 3, 3: 1, 4: 1, 5: 2, 6: 1, 7: 1, 8: 1, 9: 1}
assert frequency_lists([[1,2,3,4],[5,6,7,8],[9,10,11,12]])=={1: 1, 2: 1, 3: 1, 4: 1, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1,10:1,11:1,12:1}
assert frequency_lists([[20,30,40,17],[18,16,14,13],[10,20,30,40]])=={20:2,30:2,40:2,17: 1,18:1, 16: 1,14: 1,13: 1, 10: 1}</s>