what does LightingLambert_DirLightmap()?

Hi all,

I found in Lighting.cginc the function LightingLambert_DirLightmap();

 inline half4 LightingLambert_DirLightmap (SurfaceOutput s, fixed4 color, fixed4 scale, bool surfFuncWritesNormal)
 {
     UNITY_DIRBASIS
     half3 scalePerBasisVector;
     
     half3 lm = DirLightmapDiffuse (unity_DirBasis, color, scale, s.Normal, surfFuncWritesNormal, scalePerBasisVector);
     
     return half4(lm, 0);
 }

I was wondering what it does. Is it handeling the lightmaps or the lighting for the objects after the bake process?