docstr: Test that if Variable key is looked up in AWS Parameter Store
docstr_tok: ["Test","that","if","Variable","key","is","looked","up","in","AWS","Parameter","Store"]
code: def test_variable_lookup_pattern(
      self,
      mock_client,
      variable_key,
      variables_lookup_pattern,
      num_client_calls,
  ):
      """
      Test that if Variable key is looked up in AWS Parameter Store
      """
      mock_client().get_parameter.return_value = {
          "Parameter": {
              "Value": None,
          },
      }
      kwargs = {"variables_lookup_pattern": variables_lookup_pattern}
  
      secrets_manager_backend = SystemsManagerParameterStoreBackend(
          **kwargs
      )
      secrets_manager_backend.get_variable(variable_key)
      assert mock_client().get_parameter.call_count == num_client_calls
  
imports: from __future__ import annotations
  import json
  from unittest import mock
  import pytest
  from moto import mock_ssm
  from airflow.configuration import initialize_secrets_backends
  from airflow.providers.amazon.aws.secrets.systems_manager import SystemsManagerParameterStoreBackend
  from tests.test_utils.config import conf_vars
label_desc: Use image node_id 13 for calling the TestSsmSecrets obj's underlying member method code with example usage: obj.test_variable_lookup_pattern(mock_client, variable_key, variables_lookup_pattern, num_client_calls) without return types