Extracting additional data from a python callback function / Multiple sliders with a single callback

I have multiple sliders set up in dictionary.
Using a python callback function, i’d like to know which of the sliders has been changed - is this possible (or essentially, pass more than just the ‘value’)?

I tried creating a callback func for the gridplot object however that did not take me anywhere.

code below / thanks

from bokeh.io import show, output_notebook
from bokeh.server.server import Server
from bokeh.application import Application
from bokeh.application.handlers.function import FunctionHandler
from bokeh.models.widgets import Slider
from bokeh.layouts import gridplot

def make_doc (doc):    
    sliders = {}
    keys = ['a', 'b', 'c', 'd', 'e', 'g']
    for i in keys:
        sliders[i] = Slider (start=0, end=10, value=5, step=1, title=i)

    def callback(attr, old, new):
        print (new)
        #how do i access other slider attributes here (e.g. 'title')? 
    for slider in sliders.values():
        slider.on_change('value', callback)
    sliderGrid =  gridplot([i for i in sliders.values()], ncols=2)

handler = FunctionHandler(make_doc)
app = Application(handler)
server = Server(app, port=5000)

For something like this I use functools.partial to bake in extra parameters:

from functools import partial

def callback(attr, old, new, title):

for slider in sliders.values():
                     partial(callback, title=slider.title))