# Write a Pandas program to construct a series using the MultiIndex levels as the column and index.  
import pandas as pd 
import numpy as np
sales_arrays = [['sale1', 'sale1', 'sale2', 'sale2', 'sale3', 'sale3', 'sale4', 'sale4'],
          ['city1', 'city2', 'city1', 'city2', 'city1', 'city2', 'city1', 'city2']]
sales_tuples = list(zip(*sales_arrays))
print("Create a MultiIndex:")
sales_index = pd.MultiIndex.from_tuples(sales_tuples, names=['sale', 'city'])
print(sales_tuples)
print("\nConstruct a series using the said MultiIndex levels: ")
s = pd.Series(np.random.randn(8), index = sales_index)
print(s)
