How to merge two data frame to calculate effective spread in bond market in python

Question

I want to compute Effective spread on bond market.(It is a little bit complex)

I have 2 data frame first is Trade and the Second is quote:

Trade(Transaction) is look like this:

    Id                  Date      Index Time    Volume  Price
 0  56033738624803469   2017-05-21  1   10:32:28    1   935049.7
 1  56033738624803469   2017-05-21  1   11:54:41    10  919410.0
 2  56033738624803469   2017-05-21  2   12:25:46    1   919410.0
 3  56033738624803469   2017-05-21  1   11:48:08    5   954999.0
 4  56033738624803469   2017-05-21  2   11:48:43    6   954999.0
 5  56033738624803469   2017-05-21  1   10:00:49    50000 959900.0

and quote(Limit Order Book) is like this:

      BuyCount  BuyPrice   BuyTime  BuyVol  Date         SID              row   SellTime    SellPrice   SellVol SellCount   row.1   Quote-Spread    MidQuote
            1   930100     10:30:05 100   2017-05-21    56033738624803469   1   10:32:27    939999      5700    2            1      0.010643      935049.5
            1   930000     10:30:05 260   2017-05-21    56033738624803469   2   06:12:52    940000      2817    1            2      0.010753      935000.0
            1   928000     10:30:05 2892  2017-05-21    56033738624803469   3   06:12:52    946800      458     1            3      0.020259      937400.0
            2   900000     10:30:05 35000 2017-05-21    56033738624803469   4   06:12:52    946980      6000    1            4      0.052200      923490.0
            1   874001     10:30:05 100   2017-05-21    56033738624803469   5   06:12:52    946999      6000    1            5      0.083522      910500.0

Effective Spread is calculated like this:

  market order:  2×|pt−mt|     (absolute differention) 

Where pt is the price for the transaction at time t , and mt is the mid quote at time t−ε (just before the trade).

I should first merge this two data by time and then calculate the Effective Spread; for example: for data that been traded(First data frame) at time 10:32:28 this formula should be like this:

   Effective Spread = 2*(935049.7-935049.5).abs()

Note 1: the mid quote of row == 1 is considered and other quotes should be neglected.because markets actual trade(best buy and best sell price is in row 1)

My question is how can i merge this two data then i could calculate this formula.

Edit:

I have found this link but i my data is a little bit different.

http://www.vincentgregoire.com/introduction-to-empirical-market-microstructure-in-python/

I could not understand how to apply this to my data frame (because of Note 1)