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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 list_deployments(self):
 """List all running deployments. :returns: list of deployments :rtype: list[:class:`marathon.models.deployment.MarathonDeployment`] """

        response = self._do_request('GET', '/v2/deployments')
        return self._parse_response(response, MarathonDeployment, is_list=True)