class_docstr: Test the MWSL1BFile reader.
docstr: Test getting the platform name.
docstr_tok: ["Test","getting","the","platform","name","."]
code: def test_platform_name(self, reader):
      """Test getting the platform name."""
      assert reader.platform_name == "Metop-SG-A1"
  
imports: import logging
  from datetime import datetime
  from unittest.mock import patch
  import numpy
  import pytest
  import xarray
  from netCDF4 import Dataset
  from satpy.readers.mws_l1b import MWSL1BFile, get_channel_index_from_name
label_desc: Use image node_id 4 for calling the TestMwsL1bNCFileHandler obj's underlying member method code with example usage: obj.test_platform_name(reader) without return types