code: def new_get_hd(instance, hdr_info):
      """Generate some metadata."""
      instance.mda = {"spectral_channel_id": 1}
      instance.mda.setdefault("number_of_bits_per_pixel", 10)
  
      instance.mda["projection_parameters"] = {
          "a": 6378169.00,
          "b": 6356583.80,
          "h": 35785831.00,
          "SSP_longitude": 0.0,
      }
      instance.mda["orbital_parameters"] = {}
      instance.mda["total_header_length"] = 12
  
file_path: satpy/satpy/tests/reader_tests/test_seviri_l1b_hrit_setup.py
imports: from datetime import datetime
  from unittest import mock
  import numpy
  from satpy.readers.seviri_l1b_hrit import HRITMSGFileHandler, HRITMSGPrologueFileHandler
  from satpy.tests.reader_tests.test_seviri_base import ORBIT_POLYNOMIALS
label_desc: Use image node_id 1 for calling a global function with example usage: new_get_hd(instance, hdr_info) without return types