Looking to merge two Excel files by ID into one Excel file using Python 2.7

Question

I am new to the Python family and have been trying to solve merge two Excel files for days. I have researched merging endlessly and tried to adapt my code to fit my needs,

Answer 1

While we could fix your code, I'd strongly recommend looking into the pandas library if you're going to be doing this sort of work instead. It makes life a lot easier, and often borderline trivial.

For example, if we had two csv files (although we could have started straight from Excel files if we wanted):

>>> !cat scores3.csv
ID,JanSales,FebSales
1,100,200
2,200,500
3,300,400
>>> !cat scores4.csv
ID,CreditScore,EMMAScore
2,good,Watson
3,okay,Thompson
4,not-so-good,NA

We could read these into objects called DataFrames (think of them sort of like Excel sheets):

>>> import pandas as pd
>>> s3 = pd.read_csv("scores3.csv")
>>> s4 = pd.read_csv("scores4.csv")
>>> s3
   ID  JanSales  FebSales
0   1       100       200
1   2       200       500
2   3       300       400
>>> s4
   ID  CreditScore EMMAScore
0   2         good    Watson
1   3         okay  Thompson
2   4  not-so-good       NaN

And then we can merge them on the ID column:

>>> merged = s3.merge(s4, on="ID", how="outer")
>>> merged
   ID  JanSales  FebSales  CreditScore EMMAScore
0   1       100       200          NaN       NaN
1   2       200       500         good    Watson
2   3       300       400         okay  Thompson
3   4       NaN       NaN  not-so-good       NaN

After which we could save it to a csv file or to an Excel file:

>>> merged.to_csv("merged.csv")
>>> merged.to_excel("merged.xlsx")