import pandas as pd
import pandas_datareader.data as pdr
def load_financial_data( start_date, end_date, output_file='', stock_symbol='GOOG' ):
if len(output_file) == 0:
output_file = stock_symbol+'_data_large.pkl'
try:
df = pd.read_pickle( output_file )
df=df[start_date:end_date]
except FileNotFoundError:
df = pdr.DataReader( stock_symbol, "yahoo", start_date, end_date )
df.to_pickle( output_file )
return df
