Why is bump map implementation missing from standard shader code?

I have a custom shader that is based on the unity standard shader (using Create -> Shader -> Standard Surface Shader).

However t$$anonymous$$s shader is missing bump map properties like height map and normal map. But if I create a material and apply the standard shader, it has bump maps. Why is there a diference in the standard shader when creating a shader, and the standard shader when applying it to a material?

Is there a way to access the actual full code of the standard shader so that I can easily implement bump maps to a custom shader?