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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 find_slots(cls):
 """Return a set of all slots for a given class and its parents"""


    slots = set()
    for c in cls.__mro__:
        cslots = getattr(c, "__slots__", tuple())

        if not cslots:
            continue
        elif isinstance(cslots, (bstr, ustr)):
            cslots = (cslots,)

        slots.update(cslots)

    return slots