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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 assemble(self):
 """ Assemble a build """

        if not self.created:
            self.create()
        # trigger the build
        url = self._vr._build_url(self.resource_uri, 'build/')
        resp = self._vr.session.post(url)
        resp.raise_for_status()