erset_node_almost.py

import bpy

ng = bpy.data.materials['Material'].node_tree
mapping = ng.nodes['Mapping']

def list_props(node):
    ignored = {'bl_icon', 'bl_static_type', 'type'}
    for i in node.bl_rna.properties:
        if i.identifier in ignored:
            continue
        if hasattr(i, 'default'):
            name = i.identifier
            setattr(node, name, i.default)

list_props(mapping)