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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 add(self):
 """Add service definition to hierarchy."""


        yield self.client.create(self.path)
        yield self.client.create(self.path + "/type", self.name)
        yield self.client.create(self.path + "/state")
        yield self.client.create(self.path + "/machines", "[]")

        log.debug("registered service '%s' at %s." % (self.name, self.path))