text: import netCDF4
  
  
  def create_dummy_netcdf(tmp_path):
      """Create blank NetCDF4 file."""
      d = tmp_path / 'netcdf_files'
      try:
          d.mkdir()
      except Exception:
          pass
      p = d / 'dummy.nc'
      f = netCDF4.Dataset(p, "w", format="NETCDF4")
      f.createVariable('test', 'f4')
      f.close()
      return p
  
  
  def create_dummy_txt_file(tmp_path):
      """Create a dummy text file."""
      d = tmp_path / 'txt_files'
      try:
          d.mkdir()
      except Exception:
          pass
      p = d / 'dummy.txt'
      _fobj = open(p, 'x')
      _fobj.close()
      return p
  