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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 flatlist_dropdup(list_of_lists):
 """Make a single list out of a list of lists, and drop all duplicates. Args: list_of_lists: List of lists. Returns: list: List of single objects. """

    return list(set([str(item) for sublist in list_of_lists for item in sublist]))