How to use the beancount.query.query_compile.EvalFunction function in beancount

return inv.reduce(convert.convert_position, currency, context.price_map, date)


class ValueInventory(query_compile.EvalFunction):
    "Coerce an inventory to its market value at the current date."
    __intypes__ = [inventory.Inventory]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        inv = args[0]
        return inv.reduce(convert.get_value, context.price_map, None)

class ValueInventoryWithDate(query_compile.EvalFunction):
    "Coerce an inventory to its market value at a particular date."
    __intypes__ = [inventory.Inventory, datetime.date]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        inv, date = args
        return inv.reduce(convert.get_value, context.price_map, date)


class Price(query_compile.EvalFunction):
    "Fetch a price for something at a particular date"
    __intypes__ = [str, str]

# Note: Don't provide this, because polymorphic multiplication on Amount,
# Position, Inventory isn't supported yet.
#
# class AccountSign(query_compile.EvalFunction):
#     "Produce a +1 / -1 signed value to multiply with to correct balances."
#     __intypes__ = [str]
#
#     def __init__(self, operands):
#         super().__init__(operands, Decimal)
#
#     def __call__(self, context):
#         args = self.eval_args(context)
#         return Decimal(account_types.get_account_sign(args[0], context.account_types))

class CurrencyMeta(query_compile.EvalFunction):
    "Get the metadata dict of the commodity directive of the currency."
    __intypes__ = [str]

    def __init__(self, operands):
        super().__init__(operands, dict)

    def __call__(self, context):
        args = self.eval_args(context)
        commodity_entry = context.commodity_map.get(args[0], None)
        if commodity_entry is None:
            return {}
        return commodity_entry.meta


# Operation on inventories, positions and amounts.

return convert.get_value(pos, context.price_map, None)

class ValuePositionWithDate(query_compile.EvalFunction):
    "Convert a position to its cost currency at the market value of a particular date."
    __intypes__ = [position.Position, datetime.date]

    def __init__(self, operands):
        super().__init__(operands, amount.Amount)

    def __call__(self, context):
        args = self.eval_args(context)
        pos, date = args
        return convert.get_value(pos, context.price_map, date)


class ConvertInventory(query_compile.EvalFunction):
    "Coerce an inventory to a particular currency."
    __intypes__ = [inventory.Inventory, str]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        inv, currency = args
        return inv.reduce(convert.convert_position, currency, context.price_map, None)

class ConvertInventoryWithDate(query_compile.EvalFunction):
    "Coerce an inventory to a particular currency."
    __intypes__ = [inventory.Inventory, str, datetime.date]

    def __init__(self, operands):

def __call__(self, context):
        args = self.eval_args(context)
        return account.root(args[1], args[0])

class Parent(query_compile.EvalFunction):
    "Get the parent name of the account."
    __intypes__ = [str]

    def __init__(self, operands):
        super().__init__(operands, str)

    def __call__(self, context):
        args = self.eval_args(context)
        return account.parent(args[0])

class Leaf(query_compile.EvalFunction):
    "Get the name of the leaf subaccount."
    __intypes__ = [str]

    def __init__(self, operands):
        super().__init__(operands, str)

    def __call__(self, context):
        args = self.eval_args(context)
        return account.leaf(args[0])

class Grep(query_compile.EvalFunction):
    "Match a group against a string and return only the matched portion."
    __intypes__ = [str, str]

    def __init__(self, operands):
        super().__init__(operands, str)

class LinksEntryColumn(query_compile.EvalColumn):
    "The set of links of the transaction."
    __equivalent__ = 'entry.links'
    __intypes__ = [data.Transaction]

    def __init__(self):
        super().__init__(set)

    def __call__(self, context):
        return (context.entry.links or EMPTY_SET
                if isinstance(context.entry, Transaction)
                else EMPTY_SET)



class MatchAccount(query_compile.EvalFunction):
    """A predicate, true if the transaction has at least one posting matching
    the regular expression argument."""
    __intypes__ = [str]

    def __init__(self, operands):
        super().__init__(operands, bool)

    def __call__(self, context):
        pattern = self.eval_args(context)[0]
        search = re.compile(pattern, re.IGNORECASE).search
        return any(search(account) for account in getters.get_entry_accounts(context.entry))


# Functions defined only on entries.
ENTRY_FUNCTIONS = {
    'has_account' : MatchAccount,

__intypes__ = [Decimal, Decimal]

    def __init__(self, operands):
        super().__init__(operands, Decimal)

    def __call__(self, context):
        args = self.eval_args(context)
        try:
            return args[0] / args[1]
        except (decimal.DivisionByZero, decimal.InvalidOperation):
            return ZERO

class SafeDivInt(SafeDiv):
    __intypes__ = [Decimal, int]

class Length(query_compile.EvalFunction):
    "Compute the length of the argument. This works on sequences."
    __intypes__ = [(list, set, str)]

    def __init__(self, operands):
        super().__init__(operands, int)

    def __call__(self, context):
        args = self.eval_args(context)
        return len(args[0])

class Str(query_compile.EvalFunction):
    "Convert the argument to a string."
    __intypes__ = [object]

    def __init__(self, operands):
        super().__init__(operands, str)

return convert.convert_amount(amount_, currency, context.price_map, None)

class ConvertAmountWithDate(query_compile.EvalFunction):
    "Coerce an amount to a particular currency."
    __intypes__ = [amount.Amount, str, datetime.date]

    def __init__(self, operands):
        super().__init__(operands, amount.Amount)

    def __call__(self, context):
        args = self.eval_args(context)
        amount_, currency, date = args
        return convert.convert_amount(amount_, currency, context.price_map, date)


class ConvertPosition(query_compile.EvalFunction):
    "Coerce an amount to a particular currency."
    __intypes__ = [position.Position, str]

    def __init__(self, operands):
        super().__init__(operands, amount.Amount)

    def __call__(self, context):
        args = self.eval_args(context)
        pos, currency = args
        return convert.convert_position(pos, currency, context.price_map, None)

class ConvertPositionWithDate(query_compile.EvalFunction):
    "Coerce an amount to a particular currency."
    __intypes__ = [position.Position, str, datetime.date]

    def __init__(self, operands):

class MaxWidth(query_compile.EvalFunction):
    "Convert the argument to a substring. This can be used to ensure maximum width"
    __intypes__ = [str, int]

    def __init__(self, operands):
        super().__init__(operands, str)

    def __call__(self, context):
        string, width = self.eval_args(context)
        return textwrap.shorten(string, width=width)


# Operations on dates.

class Year(query_compile.EvalFunction):
    "Extract the year from a date."
    __intypes__ = [datetime.date]

    def __init__(self, operands):
        super().__init__(operands, int)

    def __call__(self, context):
        args = self.eval_args(context)
        return args[0].year

class Month(query_compile.EvalFunction):
    "Extract the month from a date."
    __intypes__ = [datetime.date]

    def __init__(self, operands):
        super().__init__(operands, int)

return inv.reduce(convert.convert_position, currency, context.price_map, None)

class ConvertInventoryWithDate(query_compile.EvalFunction):
    "Coerce an inventory to a particular currency."
    __intypes__ = [inventory.Inventory, str, datetime.date]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        inv, currency, date = args
        return inv.reduce(convert.convert_position, currency, context.price_map, date)


class ValueInventory(query_compile.EvalFunction):
    "Coerce an inventory to its market value at the current date."
    __intypes__ = [inventory.Inventory]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        inv = args[0]
        return inv.reduce(convert.get_value, context.price_map, None)

class ValueInventoryWithDate(query_compile.EvalFunction):
    "Coerce an inventory to its market value at a particular date."
    __intypes__ = [inventory.Inventory, datetime.date]

    def __init__(self, operands):

args = self.eval_args(context)
        return convert.get_cost(args[0])

class CostInventory(query_compile.EvalFunction):
    "Get the cost of an inventory."
    __intypes__ = [inventory.Inventory]

    def __init__(self, operands):
        super().__init__(operands, inventory.Inventory)

    def __call__(self, context):
        args = self.eval_args(context)
        return args[0].reduce(convert.get_cost)


class ConvertAmount(query_compile.EvalFunction):
    "Coerce an amount to a particular currency."
    __intypes__ = [amount.Amount, str]

    def __init__(self, operands):
        super().__init__(operands, amount.Amount)

    def __call__(self, context):
        args = self.eval_args(context)
        amount_, currency = args
        return convert.convert_amount(amount_, currency, context.price_map, None)

class ConvertAmountWithDate(query_compile.EvalFunction):
    "Coerce an amount to a particular currency."
    __intypes__ = [amount.Amount, str, datetime.date]

    def __init__(self, operands):