Processes a list of splits by modifying any positions as needed.

        Parameters
        ----------
        splits: list[(Asset, float)]
            A list of splits. Each split is a tuple of (asset, ratio).

def process_splits(self, splits):
        """Processes a list of splits by modifying any positions as needed.

        Parameters
        ----------
        splits: list[(Asset, float)]
            A list of splits. Each split is a tuple of (asset, ratio).
        """
        leftover_cash = self.position_tracker.handle_splits(splits)
        if leftover_cash > 0:
            self._cash_flow(leftover_cash)