code: def test_create_from_string_content(self):
      self._test_in_memory_file("some_content", expected_ext="txt")
      self._test_in_memory_file(
          "some_content", expected_ext="png", custom_extension="png"
      )
  
imports: import pickle
  import unittest
  from io import BytesIO, StringIO
  import numpy
  from bokeh.plotting import figure
  from PIL import Image
  from neptune.exceptions import NeptuneException, StreamAlreadyUsedException
  from neptune.internal.types.file_types import FileType, InMemoryComposite
  from neptune.internal.utils.images import _get_pil_image_data
  from neptune.types import File
  from tests.e2e.utils import tmp_context
label_desc: Use image node_id 6 for calling the TestFile obj's underlying member method code with example usage: obj.test_create_from_string_content() without return types