code: def test_just_key():
      # the filter will be ignored as the condition is not well-formed
      response = request_with_validation(
          api="/collections/{collection_name}/points/search",
          method="POST",
          path_params={"collection_name": collection_name},
          body={
              "vector": [0.2, 0.1, 0.9, 0.7],
              "limit": 3,
              "filter": {
                  "must": [
                      {
                          "key": "city",
                      }
                  ]
              },
          },
      )
      assert not response.ok
      assert response.status_code == 422
      error = response.json()["status"]["error"]
      assert "Validation error in JSON body" in error
      assert "At least one field condition must be specified" in error
  
imports: import pytest
  from .helpers.collection_setup import basic_collection_setup, drop_collection
  from .helpers.helpers import request_with_validation
label_desc: Use image node_id 3 for calling a global function with example usage: test_just_key() without return types