Merging spreadsheets with the same columns and extracting rows with matching entries

[johnbernard]

import os
import pandas as pd 
cwd = os.path.abspath('K:\\ExternalLinkValidationReports\\UK\\2020-01-06')
files = os.listdir(cwd)
df = pd.DataFrame()
for file in files:
     if file.endswith('.xlsx'):
         df = df.append(pd.read_excel(file), ignore_index=True) 
df.head()
df.to_excel('Appended Reports.xlsx')

So far I've managed to create an appended report that collects and appends all the Excel files in K:\\ExternalLinkValidationReports\\UK\\2020-01-06

However, I want to modify this so that it looks for the latest modified folder in K:\\ExternalLinkValidationReports\\UK\\
rather than having to specify the exact folder each time.

I wonder if anyone knows a quick way to modify my code so that it can do this?

Many thanks!

John