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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_default_account_data(self) -> AccountData: """ This interface is used to get the default account in WalletManager. :return: an AccountData object that contain all the information of a default account. """

        for acct in self.wallet_in_mem.accounts:
            if not isinstance(acct, AccountData):
                raise SDKException(ErrorCode.other_error('Invalid account data in memory.'))
            if acct.is_default:
                return acct
        raise SDKException(ErrorCode.get_default_account_err)