performance_analytics.returns
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spice.performance_analytics.returns(returns_timeseries: Series, start_date: datetime, end_date: datetime) -> dict

   Takes daily returns data and calculates the cumulative returns.

   Parameters:
      * **returns_timeseries** -- Daily returns series indexed by
        date(datetime format)

      * **start_date** -- Start date for the holding period

      * **end_date** -- End date for the holding period

   Returns:
      * If time period > 1 year: {"annualized_return": float}

      * If time period ≤ 1 year: {"absolute_return": float}

   Return type:
      dict
