code: def get_area_extent(cfac, lfac, coff, loff, numcols, numlines):
      """Get the area extent from msg parameters."""
      xur = (numcols - coff) * 2**16 / (cfac * 1.0)
      xur = np.deg2rad(xur) * 35785831.0
      xll = (-1 - coff) * 2**16 / (cfac * 1.0)
      xll = np.deg2rad(xll) * 35785831.0
      xres = (xur - xll) / numcols
      xur, xll = xur - xres / 2, xll + xres / 2
      yll = (numlines - loff) * 2**16 / (-lfac * 1.0)
      yll = np.deg2rad(yll) * 35785831.0
      yur = (-1 - loff) * 2**16 / (-lfac * 1.0)
      yur = np.deg2rad(yur) * 35785831.0
      yres = (yur - yll) / numlines
      yll, yur = yll + yres / 2, yur - yres / 2
  
      return xll, yll, xur, yur
  
file_path: satpy/satpy/readers/nwcsaf_msg2013_hdf5.py
imports: import logging
  from datetime import datetime
  import h5py
  import numpy
  from pyresample.geometry import AreaDefinition
  from satpy.readers.hdf5_utils import HDF5FileHandler
label_desc: Use image node_id 1 for calling a global function with example usage: get_area_extent(cfac, lfac, coff, loff, numcols, numlines) and returns: xll,  yll,  xur,  yur