code: def test_mimetypes(tmp_path):
      path = str(tmp_path / "temp.pgm")
  
      with open(path, "w") as f:
          f.write("P4\n128 128\n255")
      with Image.open(path) as im:
          assert im.get_format_mimetype() == "image/x-portable-bitmap"
  
      with open(path, "w") as f:
          f.write("PyCMYK\n128 128\n255")
      with Image.open(path) as im:
          assert im.get_format_mimetype() == "image/x-portable-anymap"
  
file_path: pillow-simd/Tests/test_file_ppm.py
imports: import sys
  from io import BytesIO
  import pytest
  from PIL import Image
  from .helper import assert_image_equal_tofile, assert_image_similar, hopper
label_desc: Use image node_id 7 for calling a global function with example usage: test_mimetypes(tmp_path) without return types