class_docstr: Unit tests for utility functions in memory_media_file_storage.py
class_docstr_tok: ["Unit","tests","for","utility","functions","in","memory_media_file_storage.py"]
code: def test_get_extension_for_mimetype(
      self, mimetype: str, expected_extension: str
  ):
      result = get_extension_for_mimetype(mimetype)
      self.assertEqual(expected_extension, result)
  
imports: import unittest
  from unittest import mock
  from unittest.mock import MagicMock, mock_open
  from parameterized import parameterized
  from streamlit.runtime.media_file_storage import MediaFileKind, MediaFileStorageError
  from streamlit.runtime.memory_media_file_storage import MemoryFile, MemoryMediaFileStorage, get_extension_for_mimetype
label_desc: Use image node_id 1 for calling the MemoryMediaFileStorageUtilTest obj's underlying member method code with example usage: obj.test_get_extension_for_mimetype(mimetype, expected_extension) without return types