code: def _get_250m_data(num_scans, rows_per_scan, num_cols):
      # Set some default attributes
      def_attrs = {
          "FillValue": 65535,
          "valid_range": [0, 4095],
          "Slope": np.array([1.0] * 1),
          "Intercept": np.array([0.0] * 1),
      }
      nounits_attrs = {**def_attrs, **{"units": "NO"}}
      radunits_attrs = {**def_attrs, **{"units": "mW/ (m2 cm-1 sr)"}}
  
      data = {
          "Data/EV_250_RefSB_b1": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=nounits_attrs,
              dims=("_rows", "_cols"),
          ),
          "Data/EV_250_RefSB_b2": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=nounits_attrs,
              dims=("_rows", "_cols"),
          ),
          "Data/EV_250_RefSB_b3": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=nounits_attrs,
              dims=("_rows", "_cols"),
          ),
          "Data/EV_250_RefSB_b4": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=nounits_attrs,
              dims=("_rows", "_cols"),
          ),
          "Data/EV_250_Emissive_b24": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=radunits_attrs,
              dims=("_rows", "_cols"),
          ),
          "Data/EV_250_Emissive_b25": xr.DataArray(
              da.ones(
                  (num_scans * rows_per_scan, num_cols),
                  chunks=1024,
                  dtype=np.uint16,
              ),
              attrs=radunits_attrs,
              dims=("_rows", "_cols"),
          ),
      }
      return data
  
imports: import os
  from unittest import mock
  import dask.array
  import numpy
  import pytest
  import xarray
  from satpy.tests.reader_tests.test_hdf5_utils import FakeHDF5FileHandler
label_desc: Use image node_id 2 for calling a global function with example usage: _get_250m_data(num_scans, rows_per_scan, num_cols) and returns: data