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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 _craft_s3_keys(self):
 """ We are putting stuff into S3, were supplied the bucket. Here we craft the key of the elements we are putting up there in the internet clouds. Args: None Returns: a tuple of teplate file key and property file key """

        now = time.gmtime()
        stub = "templates/{stack_name}/{version}".format(
            stack_name=self._config.get('environment', {}).get('stack_name', None),
            version=self._config.get('codeVersion')
        )

        stub = stub + "/" + str(now.tm_year)
        stub = stub + "/" + str('%02d' % now.tm_mon)
        stub = stub + "/" + str('%02d' % now.tm_mday)
        stub = stub + "/" + str('%02d' % now.tm_hour)
        stub = stub + ":" + str('%02d' % now.tm_min)
        stub = stub + ":" + str('%02d' % now.tm_sec)

        if self._yaml:
            template_key = stub + "/stack.yaml"
        else:
            template_key = stub + "/stack.json"

        property_key = stub + "/stack.properties"
        return template_key, property_key