class_docstr: Test Sentinel-3 SST L2 reader.
docstr: Create a 'fake' testdata set in a tar file.
docstr_tok: ["Create","a","'fake","'","testdata","set","in","a","tar","file","."]
code: def _create_tarfile_with_testdata(self, mypath):
      """Create a 'fake' testdata set in a tar file."""
      slstr_fakename = "S3A_SL_2_WST_MAR_O_NR_003.SEN3"
      tarfile_fakename = "S3A_SL_2_WST_MAR_O_NR_003.SEN3.tar"
  
      slstrdir = mypath / slstr_fakename
      slstrdir.mkdir(parents=True, exist_ok=True)
      tarfile_path = mypath / tarfile_fakename
  
      ncfilename = slstrdir / "L2P_GHRSST-SSTskin-202204131200.nc"
      self.fake_dataset.to_netcdf(os.fspath(ncfilename))
      xmlfile_path = slstrdir / "xfdumanifest.xml"
      xmlfile_path.touch()
  
      with tarfile.open(name=tarfile_path, mode="w") as tar:
          tar.add(
              os.fspath(ncfilename),
              arcname=Path(slstr_fakename) / ncfilename.name,
          )
          tar.add(
              os.fspath(xmlfile_path),
              arcname=Path(slstr_fakename) / xmlfile_path.name,
          )
  
      return tarfile_path
  
file_path: satpy/satpy/tests/reader_tests/test_ghrsst_l2.py
imports: import os
  import tarfile
  from datetime import datetime
  from pathlib import Path
  import numpy
  import pytest
  import xarray
  from satpy.readers.ghrsst_l2 import GHRSSTL2FileHandler
label_desc: Use image node_id 2 for calling the TestGHRSSTL2Reader obj's underlying member method code with example usage: obj._create_tarfile_with_testdata(mypath) and returns: tarfile_path