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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 authenticate_cinder_admin(self, keystone, api_version=2):
 """Authenticates admin user with cinder."""

        self.log.debug('Authenticating cinder admin...')
        _clients = {
            1: cinder_client.Client,
            2: cinder_clientv2.Client}
        return _clients[api_version](session=keystone.session)