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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_certificate(self, certificate_id):
 """Get certificate by id. :param str certificate_id: The certificate id (Required) :returns: Certificate object :rtype: Certificate """

        api = self._get_api(iam.DeveloperApi)
        certificate = Certificate(api.get_certificate(certificate_id))
        self._extend_certificate(certificate)
        return certificate