Fix typo

Author: dabeaz

Notes/02_Working_with_data/02_Containers.md

@@ -315,7 +315,7 @@ Experiment with this new function in the same manner as you did in
 Exercise 2.4.
 
 ```python
->>> portfolio = read_portfolio('portfolio.csv')
+>>> portfolio = read_portfolio('Data/portfolio.csv')
 >>> portfolio
 [{'name': 'AA', 'shares': 100, 'price': 32.2}, {'name': 'IBM', 'shares': 50, 'price': 91.1},
     {'name': 'CAT', 'shares': 150, 'price': 83.44}, {'name': 'MSFT', 'shares': 200, 'price': 51.23},