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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_all_slots(class_):
 """ Return a list of slot names for slots defined in class_ and its superclasses. """

    # A subclass's __slots__ attribute does not contain slots defined
    # in its superclass (the superclass' __slots__ end up as
    # attributes of the subclass).
    all_slots = []
    parent_param_classes = [c for c in classlist(class_)[1::]]
    for c in parent_param_classes:
        if hasattr(c,'__slots__'):
            all_slots+=c.__slots__
    return all_slots