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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def list_element_combinations_variadic( elements_specification ):
 """ This function accepts a specification of lists of elements for each place in lists in the form of a list, the elements of which are lists of possible elements and returns a list of lists corresponding to the combinations of elements of the specification with varying numbers of elements. For example, the list elements specification [[10, 20], [30, 40], [50, 60]] yields the following lists: [10] [20] [10, 30] [10, 40] [20, 30] [20, 40] [10, 30, 50] [10, 30, 60] [10, 40, 50] [10, 40, 60] [20, 30, 50] [20, 30, 60] [20, 40, 50] [20, 40, 60] """


    lists = [list(list_generated) for index, element_specification in enumerate(elements_specification) for list_generated in itertools.product(*elements_specification[:index + 1])]
    return lists