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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 BalanceFor(self, assetId):
 """ Get the balance for a given asset id. Args: assetId (UInt256):
 Returns: Fixed8: balance value. """

        for key, fixed8 in self.Balances.items():
            if key == assetId:
                return fixed8
        return Fixed8(0)