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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Introduction
Simply the first step to prepare the data for the following notebooks
Step1:  Data source is http
Step2:  Can also migrate it to a sqlite database
Step3:  Can perform queries
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Python Code:
import Quandl
import pandas as pd
import numpy as np
import blaze as bz
Explanation: Introduction
Simply the first step to prepare the data for the following notebooks
End of explanation
with open('../.quandl_api_key.txt', 'r') as f:
    api_key = f.read()
db = Quandl.get("EOD/DB", authtoken=api_key)
bz.odo(db['Rate'].reset_index(), '../data/db.bcolz')
fx = Quandl.get("CURRFX/EURUSD", authtoken=api_key)
bz.odo(fx['Rate'].reset_index(), '../data/eurusd.bcolz')
Explanation: Data source is http://www.quandl.com.
We use blaze to store data.
End of explanation
bz.odo('../data/db.bcolz', 'sqlite:///osqf.db::db')
%load_ext sql
%%sql sqlite:///osqf.db
select * from db
Explanation: Can also migrate it to a sqlite database
End of explanation
d = bz.Data('../data/db.bcolz')
d.Close.max()
Explanation: Can perform queries
End of explanation
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