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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 build_response(description, resource=None):
 """ Build a response definition. """

    response = swagger.Response(
        description=description,
    )
    if resource is not None:
        response.schema = swagger.JsonReference({
            "$ref": "#/definitions/{}".format(type_name(name_for(resource))),
        })
    return response