def comment(user_obj, comment_str, obj_id, coll_name):
"""
Shortcut function for instantiating and commenting
on an arbitrary object
:param user_obj:
:param comment_str:
:param obj_id:
:param coll_name:
:return comment_obj_id:
"""
comment_obj = Comment()
comment_obj.user_id = user_obj._id
comment_obj.comment = comment_str
comment_obj.coll_name = coll_name
comment_obj.obj_id = obj_id
return save(comment_obj)