code: def _extract_local_mean_gauss(
      image, mask=slice(None), sigma=1, voxelspacing=None
  ):
      """
      Internal, single-image version of `local_mean_gauss`.
      """
      # set voxel spacing
      if voxelspacing is None:
          voxelspacing = [1.0] * image.ndim
  
      # determine gaussian kernel size in voxel units
      sigma = _create_structure_array(sigma, voxelspacing)
  
      return _extract_intensities(gaussian_filter(image, sigma), mask)
  
imports: import numpy
  from scipy.ndimage import gaussian_filter, median_filter
  from scipy.ndimage import gaussian_gradient_magnitude
  from scipy.interpolate.interpolate import interp1d
  from scipy.ndimage import distance_transform_edt
  from scipy.ndimage._ni_support import _get_output
  from .utilities import join
  from ..core import ArgumentError
  from ..filter import sum_filter
label_desc: Use image node_id 18 for calling a global function with example usage: _extract_local_mean_gauss(image, mask, sigma, voxelspacing) and returns: _extract_intensities