code: def nc_filename(tmp_path):
      """Create an nc test data file and return its filename."""
      now = datetime.datetime.utcnow()
      filename = f"VGAC_VJ10XMOD_A{now:%Y%j_%H%M}_n004946_K005.nc"
      filename_str = str(tmp_path / filename)
      # Create test data
      with Dataset(filename_str, "w") as nc:
          nscn = 7
          npix = 800
          n_lut = 12000
          nc.createDimension("npix", npix)
          nc.createDimension("nscn", nscn)
          nc.createDimension("n_lut", n_lut)
          nc.StartTime = "2023-03-28T09:08:07"
          nc.EndTime = "2023-03-28T10:11:12"
          for ind in range(1, 11, 1):
              ch_name = "M{:02d}".format(ind)
              r_a = nc.createVariable(
                  ch_name, np.int16, dimensions=("nscn", "npix")
              )
              r_a[:] = np.ones((nscn, npix)) * 10
              attrs = {"scale_factor": 0.1, "units": "percent"}
              for attr in attrs:
                  setattr(r_a, attr, attrs[attr])
          for ind in range(12, 17, 1):
              ch_name = "M{:02d}".format(ind)
              tb_b = nc.createVariable(
                  ch_name, np.int16, dimensions=("nscn", "npix")
              )
              tb_b[:] = np.ones((nscn, npix)) * 800
              attrs = {"units": "radiances", "scale_factor": 0.002}
              for attr in attrs:
                  setattr(tb_b, attr, attrs[attr])
              tb_lut = nc.createVariable(
                  ch_name + "_LUT", np.float32, dimensions=("n_lut")
              )
              tb_lut[:] = np.array(range(0, n_lut)) * 0.5
      return filename_str
  
imports: import datetime
  import numpy
  import pytest
  from netCDF4 import Dataset
label_desc: Use image node_id 1 for calling a global function with example usage: nc_filename(tmp_path) and returns: filename_str