code: def test_mongo_observer_artifact_event_content_type_not_overwritten(
      mongo_obs, sample_run
  ):
      """Test that manually set content_type is not overwritten by automatic detection."""
      mongo_obs.started_event(**sample_run)
  
      filename = "setup.py"
      name = "mysetup"
  
      mongo_obs.artifact_event(
          name, filename, content_type="application/json"
      )
  
      file = mongo_obs.fs.find_one({})
      assert file.content_type == "application/json"
  
      db_run = mongo_obs.runs.find_one()
      assert db_run["artifacts"]
  
imports: import datetime
  import os
  import sys
  from glob import glob
  import mock
  import pytest
  from sacred.metrics_logger import ScalarMetricLogEntry, linearize_metrics
  import gridfs
  from mongomock.gridfs import enable_gridfs_integration
  from .failing_mongo_mock import FailingMongoClient
  from sacred.dependencies import get_digest
  from sacred.observers.mongo import MongoObserver, force_bson_encodeable
label_desc: Use image node_id 26 for calling a global function with example usage: test_mongo_observer_artifact_event_content_type_not_overwritten(mongo_obs, sample_run) without return types