code: def set_voxel_spacing(hdr, spacing):
      r"""
      Sets the voxel spacing in an image header.
  
      Notes
      -----
      It is recommended to call `hdr.set_voxel_spacing()` instead
      of this function.
  
      Parameters
      ----------
      hdr : medpy.io.Header
          An image header as returned by `load`.
      pixel_spacing : tuple of floats
          The desired pixel spacing.
      """
      hdr.set_voxel_spacing(spacing)
  
imports: import warnings
  import numpy
  from ..core import Logger
label_desc: Use image node_id 4 for calling a global function with example usage: set_voxel_spacing(hdr, spacing) without return types