code: def get_observation_time(point, scan_params):
      """Calculate observation time of a VISSR pixel."""
      relative_time = _get_relative_observation_time(point, scan_params)
      return scan_params.start_time_of_scan + relative_time
  
imports: from collections import namedtuple
  import dask.array
  import numba
  import numpy
  from satpy.utils import get_legacy_chunk_size
label_desc: Use image node_id 6 for calling a global function with example usage: get_observation_time(point, scan_params) and returns: unknown