import pandas as pd

df = pd.read_csv('lifeexpectancy-pivot.csv')

df.columns

df.values

le = pd.melt(df, id_vars=['Country','Country Code']) 

le.columns

le.values

le2 = le.rename(columns={ 'variable':'year','value':'life_expectancy'}).sort('Country')

le2.columns

le2.values

le2.to_csv('lifeexpectancy-unpivoted.csv', sep=',', index=False)