blender/release/scripts/templates/operator_simple.py

import bpy


def main(context):
    for ob in context.scene.objects:
        print(ob)


class SimpleOperator(bpy.types.Operator):
    '''Tooltip'''
    bl_idname = "object.simple_operator"
    bl_label = "Simple Object Operator"

    @classmethod
    def poll(cls, context):
        return context.active_object != None

    def execute(self, context):
        main(context)
        return {'FINISHED'}


if __name__ == "__main__":
    bpy.ops.object.simple_operator()