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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_uuid(obj):
 """Return the uuid for obj, or null uuid if none is set"""

    # TODO: deprecate null uuid ret val
    from uuid import UUID
    try:
        uuid = obj.attrs['uuid']
    except KeyError:
        return UUID(int=0)
    # convert to unicode for python 3
    try:
        uuid = uuid.decode('ascii')
    except (LookupError, AttributeError):
        pass
    return UUID(uuid)