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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 balance(self, as_of=None, raw=False, leg_query=None, **kwargs):
 """Get the balance for this account, including child accounts Args: as_of (Date):
 Only include transactions on or before this date raw (bool):
 If true the returned balance should not have its sign adjusted for display purposes. kwargs (dict):
 Will be used to filter the transaction legs Returns: Balance See Also: :meth:`simple_balance()` """

        balances = [
            account.simple_balance(as_of=as_of, raw=raw, leg_query=leg_query, **kwargs)
            for account in self.get_descendants(include_self=True)
        ]
        return sum(balances, Balance())