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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_benchmark_returns(symbol):
 """ Get a Series of benchmark returns from IEX associated with `symbol`. Default is `SPY`. Parameters symbol : str Benchmark symbol for which we're getting the returns. The data is provided by IEX (https://iextrading.com/), and we can get up to 5 years worth of data. """

    r = requests.get(
        'https://api.iextrading.com/1.0/stock/{}/chart/5y'.format(symbol)
    )
    data = r.json()

    df = pd.DataFrame(data)

    df.index = pd.DatetimeIndex(df['date'])
    df = df['close']

    return df.sort_index().tz_localize('UTC').pct_change(1).iloc[1:]