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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 get_diff(left, right):
 """Get the difference of both lists. The result will be a dict with this form {'+': [], '-': []}. Items listed in '+' exist only in the right list, items listed in '-' exist only in the left list. """

    res = {'+': [], '-': []}

    def partition(objects):
        """Partition the passed object list."""
        res = {}
        for o in objects:
            t = type(o)
            if type(o) not in res:
                res[t] = []
            res[t].append(o)
        return res

    def get_not_included(foo, bar):
        """Compare objects from foo with objects defined in the values of
        bar (set of partitions).
        Returns a list of all objects included in list, but not dict values.
        """
        res = []
        for o in foo:
            if not compat.object_in_list(type(o), bar):
                res.append(o)
            elif not compat.object_in_list(o, bar[type(o)]):
                res.append(o)
        return res

    # Create partitions of both lists. This will reduce the time required for
    # the comparison
    left_objects = partition(left)
    right_objects = partition(right)
    # and then do the diff
    res['+'] = get_not_included(right, left_objects)
    res['-'] = get_not_included(left, right_objects)
    return res