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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 _docstring(self):
 """ Generate a docstring for the generated source file. :return: new docstring :rtype: str """

        s = '"""' + "\n"
        s += "webhook2lambda2sqs generated function source\n"
        s += "this code was generated by webhook2lambda2sqs v%s\n" % VERSION
        s += "<%s>\n" % PROJECT_URL
        s += "this project is licensed under the AGPLv3 open source license.\n"
        s += "\n"
        s += "DO NOT MODIFY this function; modifications should be made by "
        s += "re-running\n"
        s += "the project with an updated configuration.\n"
        s += '"""' + "\n"
        return s