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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 subclass_exception(name, parents, module, attached_to=None):
 """ Create exception subclass. If 'attached_to' is supplied, the exception will be created in a way that allows it to be pickled, assuming the returned exception class will be added as an attribute to the 'attached_to' class. """

    class_dict = {'__module__': module}
    if attached_to is not None:
        def __reduce__(self):
            # Exceptions are special - they've got state that isn't
            # in self.__dict__. We assume it is all in self.args.
            return (unpickle_inner_exception, (attached_to, name), self.args)

        def __setstate__(self, args):
            self.args = args

        class_dict['__reduce__'] = __reduce__
        class_dict['__setstate__'] = __setstate__

    return type(name, parents, class_dict)