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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 pass_multipart(with_completed=False):
 """Decorate to retrieve an object."""

    def decorate(f):
        @wraps(f)
        def inner(self, bucket, key, upload_id, *args, **kwargs):
            obj = MultipartObject.get(
                bucket, key, upload_id, with_completed=with_completed)
            if obj is None:
                abort(404, 'uploadId does not exists.')
            return f(self, obj, *args, **kwargs)
        return inner
    return decorate