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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 validate(self, asset, amount, portfolio, algo_datetime, algo_current_data):
 """ Fail if the algo has passed this Asset's end_date, or before the Asset's start date. """

        # If the order is for 0 shares, then silently pass through.
        if amount == 0:
            return

        normalized_algo_dt = pd.Timestamp(algo_datetime).normalize()

        # Fail if the algo is before this Asset's start_date
        if asset.start_date:
            normalized_start = pd.Timestamp(asset.start_date).normalize()
            if normalized_algo_dt < normalized_start:
                metadata = {
                    'asset_start_date': normalized_start
                }
                self.handle_violation(
                    asset, amount, algo_datetime, metadata=metadata)
        # Fail if the algo has passed this Asset's end_date
        if asset.end_date:
            normalized_end = pd.Timestamp(asset.end_date).normalize()
            if normalized_algo_dt > normalized_end:
                metadata = {
                    'asset_end_date': normalized_end
                }
                self.handle_violation(
                    asset, amount, algo_datetime, metadata=metadata)