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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_account_from_hash(self, account_hash):
 """ Returns the account with the given hash, if it is contained in any of the pools. Returns None otherwise. :type account_hash: str :param account_hash: The hash of an account object. """

        for _, pool in self.pools:
            account = pool.get_account_from_hash(account_hash)
            if account is not None:
                return account
        return self.default_pool.get_account_from_hash(account_hash)