In Bokeh, how do I add tooltips to a Timeseries chart (hover tool)?

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Below is what I came up with.

Its not pretty but it works.

Im still new to Bokeh (& Python for that matter) so if anyone wants to suggest a better way to do this, please feel free.

enter image description here

import pandas as pd
import numpy as np
from bokeh.charts import TimeSeries
from bokeh.models import HoverTool
from bokeh.plotting import show

toy_df = pd.DataFrame(data=np.random.rand(5,3), columns = ('a', 'b' ,'c'), index = pd.DatetimeIndex(start="01-01-2015",periods=5, freq='d'))       

 _tools_to_show = 'box_zoom,pan,save,hover,resize,reset,tap,wheel_zoom'        

p = figure(width=1200, height=900, x_axis_type="datetime", tools=_tools_to_show)


# FIRST plot ALL lines (This is a hack to get it working, why can't i pass in a dataframe to multi_line?)   
# It's not pretty but it works. 
# what I want to do!: p.multi_line(df)
ts_list_of_list = []
for i in range(0,len(toy_df.columns)):
    ts_list_of_list.append(toy_df.index.T)

vals_list_of_list = toy_df.values.T.tolist()

# Define colors because otherwise multi_line will use blue for all lines...
cols_to_use =  ['Black', 'Red', 'Lime']
p.multi_line(ts_list_of_list, vals_list_of_list, line_color=cols_to_use)


# THEN put  scatter one at a time on top of each one to get tool tips (HACK! lines with tooltips not yet supported by Bokeh?) 
for (name, series) in toy_df.iteritems():
    # need to repmat the name to be same dimension as index
    name_for_display = np.tile(name, [len(toy_df.index),1])

    source = ColumnDataSource({'x': toy_df.index, 'y': series.values, 'series_name': name_for_display, 'Date': toy_df.index.format()})
    # trouble formating x as datestring, so pre-formating and using an extra column. It's not pretty but it works.

    p.scatter('x', 'y', source = source, fill_alpha=0, line_alpha=0.3, line_color="grey")     

    hover = p.select(dict(type=HoverTool))
    hover.tooltips = [("Series", "@series_name"), ("Date", "@Date"),  ("Value", "@y{0.00%}"),]
    hover.mode="mouse"

show(p)

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