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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 simple_returns(prices):
 """ Compute simple returns from a timeseries of prices. Parameters prices : pd.Series, pd.DataFrame or np.ndarray Prices of assets in wide-format, with assets as columns, and indexed by datetimes. Returns ------- returns : array-like Returns of assets in wide-format, with assets as columns, and index coerced to be tz-aware. """

    if isinstance(prices, (pd.DataFrame, pd.Series)):
        out = prices.pct_change().iloc[1:]
    else:
        # Assume np.ndarray
        out = np.diff(prices, axis=0)
        np.divide(out, prices[:-1], out=out)

    return out