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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_quantity(self) -> Decimal: """ Returns the number of shares for the given security. It gets the number from all the accounts in the book. """

        from pydatum import Datum
        # Use today's date but reset hour and lower.
        today = Datum()
        today.today()
        today.end_of_day()
        return self.get_num_shares_on(today.value)