code: def l2_lgr_schema(settings=None):
      """Define schema for LI L2 LGR product."""
      settings = settings or {}
      ngrps = settings.get("num_groups", 120)
  
      return {
          "providers": settings.get("providers", {}),
          "variable_path": settings.get("variable_path", ""),
          "dimensions": {
              "groups": ngrps,
          },
          "variables": {
              "latitude": {
                  "format": "f4",
                  "shape": ("groups",),
                  "long_name": "Latitude of group",
                  "units": "degrees_north",
                  "default_data": lambda: np.linspace(-90, 90, ngrps),
              },
              "longitude": {
                  "format": "f4",
                  "shape": ("groups",),
                  "long_name": "Longitude of group",
                  "units": "degrees_east",
                  "default_data": lambda: np.linspace(-180, 80, ngrps),
              },
          },
      }
  
imports: from datetime import datetime
  import numpy
  import xarray
  from satpy.tests.reader_tests.test_netcdf_utils import FakeNetCDF4FileHandler
label_desc: Use image node_id 3 for calling a global function with example usage: l2_lgr_schema(settings) and returns: dict