import bpy
import os

mat = bpy.data.materials["Material"]

nodes = mat.node_tree.nodes
material_output = nodes.get ("Material Output")

node_texture = nodes.new(type='ShaderNodeTexImage')
node_texture.image = bpy.data.images.load ('C:\Users\KM\Desktop\Blender\auto.png')
node_texture.projection = "LINEAR"


links = mat.node_tree.links
link = links.new(node_texture.otputs[0], nodes.get("DIffuse BSDF"),inputs[0])