Coefficient variable for crypto assets

coingecko.py

import time
import json
import datetime
import requests
import numpy as np
import pandas as pd

headers = {'Content-Type': 'application/json'}
api_url_base_coingecko = 'https://api.coingecko.com/api/v3/coins/'
vs_currency = 'usd'
days = '30'

def getCoinData(ids, vs, days):
    api_url_coingecko = '{0}/{1}/ohlc?vs_currency={2}&days={3}'.format(api_url_base_coingecko, ids, vs, days)
    res = requests.get(api_url_coingecko, headers=headers)

    if res.status_code == 200:
        df = pd.read_json(res.content.decode('utf-8'))
        df.columns = ['timestamp', 'Open', 'High', 'Low', 'Close']
        df['timestamp'] = df['timestamp']/1000
        df['timestamp'] = df['timestamp'].astype(int)
        df['timestamp'] = df['timestamp'].map(datetime.datetime.utcfromtimestamp)
        df.index = df['timestamp']
        feature_name = ['Close']
        df = df[feature_name]
        df.interpolate(limit_direction='both', inplace=True)
        df.columns = [ids]
        return df
    else:
        return None

coins = ['bitcoin', 'ethereum', 'chainlink', 'ripple', 'litecoin', 'polkadot']
df = pd.DataFrame()
for coin in coins:
    df = pd.concat([df, getCoinData(coin, vs_currency, days)], axis=1, sort=True, join='outer')
    
df.head()