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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_diff(current, prior):
 """ Figure out what the expenditure difference is between two accounts. They must be for the same token type and address. Calculates current - prior """

    if current['address'] != prior['address'] or current['type'] != prior['type']:
        raise ValueError("Accounts for two different addresses and/or token types")

    # NOTE: only possible since Python doesn't overflow :P
    return namedb_get_account_balance(current) - namedb_get_account_balance(prior)