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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 get_existing_pipelines(self):
 """Get existing pipeline configs for specific application. Returns: str: Pipeline config json """

        url = "{0}/applications/{1}/pipelineConfigs".format(API_URL, self.app_name)
        resp = requests.get(url, verify=GATE_CA_BUNDLE, cert=GATE_CLIENT_CERT)
        assert resp.ok, 'Failed to lookup pipelines for {0}: {1}'.format(self.app_name, resp.text)

        return resp.json()