In [3]:
import pandas as pd

In [21]:
df = pd.read_csv('http://indexes.nikkei.co.jp/nkave/historical/nikkei_stock_average_daily_jp.csv')
df.columns = ['date', 'close', 'open', 'high', 'low']
df = df.dropna()

In [22]:
df.to_csv("nikkei")

In [20]:
a = df['close']

In [ ]: