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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 namedb_get_account_balance(account):
 """ Get the balance of an account for a particular type of token. This is its credits minus its debits. Returns the current balance on success. Aborts on error, or if the balance is somehow negative. """

    # NOTE: this is only possible because Python does not overflow :P
    balance = account['credit_value'] - account['debit_value']
    if balance < 0:
        log.fatal("Balance of {} is {} (credits = {}, debits = {})".format(account['address'], balance, account['credit_value'], account['debit_value']))
        traceback.print_stack()
        os.abort()

    return balance