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Duo Data Utilities: IBAN, ISIN, VAT and Tax ID, Barcode, Timezone, Geo APIs

by hiesemversion 1.0.5i★ –iRuns in the cloud
Registry namecom.duoleads.api/data-utilities

Install

Overview

Description from the maker (original English)

IBAN, ISIN, VAT/tax ID, GTIN validation; timezone, geo, text, chain utilities. Pay per call

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs in the cloud
  • Transport: Streamable HTTP
  • Category: Accounting, finance & tax

Install

Pick the AI app you use, then copy the settings.

Before you install

You need

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Works in Claude on the web, desktop and mobile:

  1. Open Settings → Connectors
  2. Press Add custom connector
  3. Paste the address below and press Add
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Add2https://…3
https://api.duoleads.com/mcp

Run this in your terminal

claude mcp add --transport http data-utilities https://api.duoleads.com/mcp

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "data-utilities": {
      "url": "https://api.duoleads.com/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "data-utilities": {
      "type": "http",
      "url": "https://api.duoleads.com/mcp"
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

ChatGPT connects only to servers on the internet:

  1. Open ChatGPT on the web → Settings → Connectors (Apps)
  2. Press Create or Add (some plans need Developer mode under Advanced first)
  3. Paste the address below, give it a name and save
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Create2https://…3
https://api.duoleads.com/mcp

Menu names can differ slightly by plan and over time.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Tool names and descriptions exactly as the server reported them on Nov 7, 2026. The maker wrote them, not us; we show them as plain text.

  • vat_tax_id_validate

    VAT, tax ID and national ID validator: check a national identity, tax or company registration number against its country's official checksum rule. Covers 23 countries including NL BSN, ES NIF/NIE/CIF, IT codice fiscale, FR SIREN/SIRET, DE Steuer-ID, BE/PL/CZ national numbers, SE/

  • gtin_barcode_validate

    GTIN barcode validator: validate and convert GS1 identifiers: GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), GTIN-14, GLN and SSCC. Returns the check-digit verdict, the computed correct check digit, the GTIN-14 form with its indicator digit, and conversion between GTIN-8, -12, -13 an

  • isin_cusip_sedol_validate

    ISIN validator plus CUSIP, SEDOL and FIGI check digits: validate the check digit of a financial security identifier (ISIN per ISO 6166). Returns the verdict, the computed correct check character, and for an ISIN the issuing country prefix and the embedded NSIN. Also builds an ISI

  • iban_validate

    IBAN validator: validate an IBAN's length for its country, permitted character classes per field, and the ISO 7064 mod-97-10 check digits. Returns the verdict with a specific failure reason, the electronic and print formats, and the decomposed bank code, branch code and account n

  • iban_generate

    IBAN generator: construct an IBAN from a country code and the domestic account parts, computing the ISO 7064 mod-97-10 check digits. Takes a single BBAN string or named parts (bank code, branch code, account number); digit fields are left-padded with zeros to the country's regist

  • timezone_convert

    Timezone converter: convert an instant to wall-clock time in a named IANA time zone, or a wall-clock time in a zone back to an instant. Returns the local date and time, the UTC offset in ±HH:MM and seconds, the zone abbreviation, whether DST is in effect, the ISO week date, and t

  • dst_transitions

    DST transitions: list the daylight-saving time changes for an IANA time zone over a date range: the exact instant of each shift, the offset before and after, and whether local clocks jump forward or back. Returns the current offset and DST state, and the next transition from a gi

  • business_days_calculate

    Business days calculator with a caller-supplied calendar: add or subtract N working days from a date, or count the working days between two dates. The weekend is a weekday mask (Friday-Saturday and Sunday-only weeks work) and holidays are an explicit date list, so nothing depends

  • rrule_expand

    RRULE expander: expand an RFC 5545 recurrence rule into concrete occurrence timestamps. Accepts an RRULE string with DTSTART, an IANA time zone, and optional EXDATE and RDATE lists, and returns up to 200 occurrences as both local wall-clock times and UTC instants. Supports FREQ,

  • calendar_convert

    Calendar converter: convert a Gregorian date to other calendar systems: Islamic (both the tabular civil calendar and the Umm al-Qura variant), Hebrew, Japanese imperial era, Republic of China, Buddhist and Persian. Also computes Easter Sunday for a year in both the Gregorian and

  • slug_generate

    Slug generator: turn arbitrary text into a URL-safe slug. Decomposes accents, transliterates German umlauts, Scandinavian and Turkish letters, the ligatures that lose meaning under plain NFD, and Cyrillic (Russian, Ukrainian, Belarusian, Bulgarian, Serbian, Macedonian; language f

  • cyrillic_transliterate

    Cyrillic transliteration to Latin using a named standard: ISO 9:1995 (one-to-one, with diacritics, covering the full standard: Russian, other Slavic, historic and non-Slavic Cyrillic letters) or BGN/PCGN, which is the Russian system only (Ukrainian, Serbian and other letters are

  • unicode_confusables_check

    Unicode normalization and confusables check: apply NFC, NFD, NFKC or NFKD, report which forms a string is already in, list the scripts present (all Unicode scripts), and flag confusable and homoglyph characters — Cyrillic а in a Latin word, fullwidth or mathematical look-alikes,

  • string_similarity

    String similarity: compare two strings and return every standard measure in one call: Levenshtein and Damerau-Levenshtein edit distance, normalised similarity, Jaro and Jaro-Winkler, longest common subsequence, Dice coefficient on character bigrams, and the Soundex, Metaphone and

  • url_parse

    URL parser: parse and canonicalise a URL, and extract its registrable domain using the Public Suffix List — the part an agent needs to decide whether two URLs belong to the same owner. Returns scheme, host, port, path, decoded query parameters and fragment, the public suffix, the

  • punycode_convert

    Punycode converter: convert internationalised domain names between Unicode and ASCII punycode in either direction, label by label, and validate each label against IDNA2008: length, leading and trailing hyphens, the hyphen-hyphen rule at positions 3 and 4, disallowed code points a

  • semver_compare

    Semver parser and comparator: parse a semantic version into major, minor, patch, prerelease and build parts; compare two versions by precedence including prerelease ordering; or test whether a version satisfies a range expression using caret, tilde, hyphen, x-ranges and comparato

  • hash_generate

    Hash generator: compute a cryptographic digest of supplied data: SHA-256, SHA-384, SHA-512, SHA-1, SHA3-256, SHA3-512, Keccak-256, BLAKE2b-256 and BLAKE2b-512, plus HMAC with any of them. Input is UTF-8 text, base64 or hex bytes; output is hex, base64, base64url or base32. Return

  • jwt_decode

    JWT decoder: decode a JSON Web Token without verifying it: returns the header, the claims, the signature length and algorithm, and a computed view of the time claims — whether exp has passed, whether nbf is in the future, and the remaining lifetime in seconds against a supplied o

  • geohash_encode_decode

    Geohash encoder and decoder: encode a WGS-84 latitude and longitude to a geohash at a chosen precision, or decode a geohash back to its bounding box, centre point and error bounds in metres. Encoding also returns the eight neighbouring cells, which is what a caller needs to do pr

  • plus_code_encode_decode

    Plus code (Open Location Code) encoder and decoder: encode coordinates as a plus code at a chosen length, or decode a full code back to its bounding box and centre. Also shortens a full code against a reference coordinate and recovers a shortened code given a reference, which is

  • point_in_polygon

    Point in polygon check and GeoJSON geometry: point-in-polygon with correct hole handling, bounding box, centroid, signed area in square metres, perimeter length, and ring winding order for a geometry supplied in the request. Accepts Polygon and MultiPolygon, and a GeoJSON Feature

  • geo_distance

    Distance calculator: distance and direction between WGS-84 coordinates: geodesic distance by Vincenty with a haversine fallback, initial and final bearing, the midpoint, and the destination point reached from a start point on a given bearing and distance. Also computes the cumula

  • crypto_address_validate

    Crypto address validator: identify which blockchain an address belongs to and validate its encoding: EVM EIP-55 checksum, Bitcoin base58check and bech32/bech32m with witness version, Solana base58 and on-curve check, Cosmos bech32 with its HRP, Tron, XRP, Litecoin, Dogecoin, Card

  • solidity_function_selector

    Solidity function selector and event topic: compute the Keccak-256 hash of a function or event signature and derive the 4-byte selector and the 32-byte topic. Normalises the signature first — strips parameter names, expands uint to uint256 and the other aliases, flattens tuples —

  • nuts_region_lookup

    NUTS region lookup (EU statistical regions): resolve a NUTS code to its name, country and level, walk up to its parents or down to its children, or search regions by name. Covers all four levels (country, major region, basic region, small region) for the 27 member states and 12 f

  • airport_lookup

    Airport lookup by IATA or ICAO code: get the airport's name, city, country, ISO 3166-2 region code, WGS-84 coordinates, elevation and IANA time zone, or find the nearest airports to a coordinate within a radius. Covers every airport worldwide that holds a three-letter IATA code a

  • currency_lookup

    Currency lookup by ISO 4217 alphabetic or numeric code: the official English name, minor-unit exponent, fund flag, the smallest cash denomination where it differs from the minor unit, the territories that use it, and historic codes on request. Returns the correct rounding increme

  • country_lookup

    Country lookup: find a country or territory by ISO 3166-1 alpha-2, alpha-3 or numeric code, or by name, and get the other codes, the official and common English names, the UN M49 region and sub-region, the currencies in use, the country-code TLD, and optionally the full ISO 3166-

  • base_convert

    Base converter: convert an integer between any two numeric bases from 2 to 36 (hex, binary, octal and more), with arbitrary precision so values far beyond 2^53 are exact. Accepts an optional sign and common prefixes (0x, 0b, 0o), validates every digit against the source base, and

  • number_to_words

    Number to words: spell a number out in English, Dutch, German, French, Spanish, Italian, Portuguese, Polish, Russian, Turkish, Swedish or Japanese, in cardinal, ordinal or currency form. Currency form agrees the number with the currency noun and gives real minor-unit names for 19

  • statistics_calculate

    Statistics calculator for a numeric array in one call: count, sum, mean, median, mode, variance and standard deviation honouring ddof (default 1, the sample form; 0 gives the population form) plus always-population *_population fields, min, max, range, the quartiles and interquar

  • money_split

    Money split: split a money amount into shares without losing or inventing a cent. Divide evenly into N parts, or by a list of ratios, and the remainder is distributed one minor unit at a time by a named, deterministic rule — largest-remainder, first-wins or last-wins — so the par

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 8, 2026

  • ! Caution

    Maker matches the repo

    The publisher (api.duoleads.com) is not the repo owner (hiesem); someone else may have listed it

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • ✓ Pass

    Endpoint responds

    Responded in 474 ms (HTTP 200)

  • – Not applicable

    Sign-in with OAuth

    No sign-in needed

  • ✓ Pass

    No hidden instructions in tool descriptions

    Read 33 tool descriptions and found no hidden instructions to the AI

Compared with others in Accounting, finance & taxi

  • More stars than 0% of the other 2913 servers in this category
  • Published to the registry more recently than 96% of the other 2913 servers in this category
  • Basic checks equal to or better than 45% of the other 2913 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Duo Data Utilities: IBAN, ISIN, VAT and Tax ID, Barcode, Timezone, Geo APIs safe?

It passed 2 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.0.5) reached the registry today.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Finance Toolkit, SolidInvoice, Korea Tax Calculator

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README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

IBAN, ISIN, VAT/tax ID and GTIN barcode validation plus 29 more utilities for AI agents. Pay per call ($0.05 USDC on Base via x402), no API key, no signup.

Timezone and DST, geo distance and geohash, hashes and JWT decoding, airport, country, currency and NUTS lookups, money split, base conversion and more. Every call is one HTTP GET, paid per request.

Also crypto derivatives data for trading agents: perp funding rates, funding arbitrage, open interest, futures basis, implied volatility, liquidations and order book depth across Bybit, Hyperliquid, dYdX, Gate, Kraken, Bitfinex, Deribit and OKX, at $0.003 or $0.005 per call (below).

Install

npm install duo-data-utilities viem

viem creates the wallet account that pays. This package also depends on it. Node.js 20 or later.

Python (not on PyPI, install from GitHub):

pip install "git+https://github.com/hiesem/duo-data-utilities#subdirectory=python"

Quick start

import { privateKeyToAccount } from "viem/accounts";

import { createClient } from "duo-data-utilities";

// Your wallet holds USDC on Base. Read the key from the environment, never a literal. const client = createClient({ account: privateKeyToAccount(process.env.DUO_PAYER_KEY as 0x${string}) });

const iban = await client.iban.validate({ iban: "NL91 ABNA 0417 1643 00" }); // $0.05 console.log(iban.valid, iban.country); // true NL

Counterparty check

checkCounterparty runs three checks in one call: IBAN (/v1/id/iban), tax ID (/v1/id/national) and country (/v1/ref/country). It costs $0.15.

const check = await client.checkCounterparty({

iban: "NL91 ABNA 0417 1643 00", country: "NL", taxIdType: "bsn", taxId: "111222333", }); console.log(check.verdict, check.reasons); // "pass", "fail" or "review"

  • fail: the IBAN or the tax ID fails its checksum, the country is not an ISO 3166-1 country, or the API rejects an input as malformed.
  • review: the IBAN country differs from the tax ID country, or the API does not cover that country or tax ID kind.
  • pass: every check passed.

Structure and checksum only. The check does not query a company register, a bank or a tax authority, and it does not confirm that an account exists. UK is read as GB.

Crypto derivatives data: perp funding rates, open interest, futures basis, implied volatility, liquidations, order book depth

client.derivs calls https://derivs.duoleads.com: crypto derivatives data from 8 exchanges (Bybit, Hyperliquid, dYdX, Gate, Kraken, Bitfinex, Deribit, OKX) for trading agents and bots. Perpetual futures (perp) funding rates with predicted funding, funding rate history and a funding arbitrage scanner, a perp screener, open interest (OI), futures basis and term structure, options implied volatility (IV), skew and max pain, liquidations, and order book depth with slippage. $0.003 or $0.005 per call, same wallet, same x402 payment, no API key.

import { privateKeyToAccount } from "viem/accounts";

import { createClient, createDerivsClient } from "duo-data-utilities";

const account = privateKeyToAccount(process.env.DUO_PAYER_KEY as 0x${string}); const client = createClient({ account });

const funding = await client.derivs.fundingRates({ coin: "BTC" }); // $0.003 for (const v of funding.venues) console.log(v.venue, v.apr_pct, v.next_funding_time);

const arb = await client.derivs.fundingArbitrage({ min_apr: 20, min_volume_usd: 1_000_000 }); // $0.005, all coins const snap = await client.derivs.derivativesSnapshot({ coin: "ETH" }); // $0.005: funding, OI, basis, liquidations, long/short

// Or a derivs-only client: const derivs = createDerivsClient({ account }); await derivs.openInterest({ coin: "SOL" }); // $0.003

import os

from eth_account import Account from duo_data_utilities import DerivsClient, DuoClient

client = DuoClient(Account.from_key(os.environ["DUO_PAYER_KEY"])) rates = client.derivs.funding_rates(coin="BTC") # $0.003 book = client.derivs.orderbook(coin="BTC", size_usd=250_000) # $0.003 derivs = DerivsClient(Account.from_key(os.environ["DUO_PAYER_KEY"])) # derivs only

  • Price guard: client.derivs has its own cap, $0.005 per call by default. createClient({ account, derivs: { maxPriceUsd: 0.003 } }) refuses the $0.005 routes (Python: derivs_max_price_usd=0.003). The other rules are the same: Base USDC only, only to 0xCD673f7e1daD254347AEab6be0DEFe8b9C6b3A39, nothing is signed before the check.
  • Not charged: bad input is a free 400 with error.expected. When fewer venues answer than the route needs, the answer is a 503 and nothing is charged. Both throw DuoApiError.
  • Answers are the JSON body itself (no data envelope), with venues_missing, units, as_of and a see_also pointer to the next useful route. TypeScript types: DerivsFundingRatesData and so on.
  • Coins: BTC, btc, BTCUSDT, BTC-PERP, XBT, 1000PEPE and kPEPE all name a coin.
  • MCP: the same 10 tools at https://derivs.duoleads.com/mcp. Snippets for Claude Code, Claude Desktop, Cursor and VS Code: mcp/README.md.
  • Data only, not investment advice, not affiliated with any exchange.
TypeScriptPythonRoutePriceWhat it returns
derivs.fundingRatesderivs.funding_rates/v1/funding-rates$0.003Perp funding rates per exchange for one coin: rate, 8h rate, APR, next funding, predicted funding (incl. Binance and Bybit), last 24 prints
derivs.fundingHistoryderivs.funding_history/v1/funding-history$0.003Funding rate history of one coin on one exchange, up to 30 days, with avg/min/max/% positive
derivs.fundingArbitragederivs.funding_arbitrage/v1/funding-arbitrage$0.005Funding arbitrage scanner for all coins: widest cross-venue spread, long and short venue, fee-adjusted net APR, breakeven days
derivs.perpScreenerderivs.perp_screener/v1/perp-screener$0.005Perp screener: every perpetual across venues, sorted by funding APR, open interest, 24h volume or 24h change
derivs.openInterestderivs.open_interest/v1/open-interest$0.003Open interest (OI) per exchange in coins and USD, share, and 1h/4h/24h OI change
derivs.basisderivs.basis/v1/basis$0.003Futures basis and term structure (annualised, contango/backwardation), perp premium, predicted funding
derivs.optionsderivs.options/v1/options$0.003Implied volatility (ATM IV), 25-delta skew, put/call OI ratio, max pain, DVOL; options chain with greeks for one expiry
derivs.liquidationsderivs.liquidations/v1/liquidations$0.003Long and short liquidations in USD per venue over 1-24h, totals and the largest events
derivs.orderbookderivs.orderbook/v1/orderbook$0.003Order book depth within 0.1/0.5/1/2% of mid, spread, imbalance, slippage for your order size, walls
derivs.derivativesSnapshotderivs.derivatives_snapshot/v1/derivatives-snapshot$0.005One-call snapshot: funding, open interest, perp premium and nearest basis, 24h liquidations, long/short ratio

Derivs docs: https://derivs.duoleads.com/docs · OpenAPI: https://derivs.duoleads.com/openapi.json · Index: https://derivs.duoleads.com/llms.txt · Terms: https://derivs.duoleads.com/terms · Privacy: https://derivs.duoleads.com/privacy

SEO keyword data: search volume, CPC, keyword difficulty, keyword ideas, Google Trends

client.keywords calls https://keywords.duoleads.com. It returns Google keyword search volume, CPC, competition, keyword difficulty and search intent (Google Ads data), keyword ideas for a seed, and Google Trends (interest over time, related queries, interest by region). Calls cost $0.03 to $0.045 each and use the same wallet and the same x402 payment, with no API key.

const volume = await client.keywords.searchVolume({ keywords: ["phone", "watch"], country: "us" }); // $0.04, up to 20 keywords

const overview = await client.keywords.keywordOverview({ keywords: myList }); // $0.04, up to 100 keywords (POST) const ideas = await client.keywords.keywordIdeas({ keyword: "seo api", limit: 50 }); // $0.04 (POST) const trend = await client.keywords.trend({ keyword: "seo tools", timeframe: "past_12_months" }); // $0.045

// Or a keywords-only client: const keywords = createKeywordsClient({ account }); await keywords.relatedQueries({ keyword: "seo api", country: "us" }); // $0.03

  • Price guard: client.keywords has its own cap, $0.045 per call by default. createClient({ account, keywords: { maxPriceUsd: 0.04 } }) refuses the $0.045 trend route. The other rules are the same: Base USDC only, only to 0xCD673f7e1daD254347AEab6be0DEFe8b9C6b3A39, and nothing is signed before the check.
  • Errors: a bad input is a free 400. An upstream failure is a 503 with "nothing was charged". Both throw DuoApiError.
  • MCP: the same 6 tools are at https://keywords.duoleads.com/mcp.
MethodRoutePriceWhat it returns
keywords.keywordOverviewPOST /v1/keyword-overview$0.04Search volume, CPC, competition, keyword difficulty and intent for 1-100 keywords
keywords.searchVolumeGET /v1/search-volume$0.04The same metrics for 1-20 keywords in one country
keywords.keywordIdeasPOST /v1/keyword-ideas$0.04Up to 100 related keyword ideas for one seed, each with the same metrics
keywords.trendGET /v1/trend$0.045Google Trends interest over time (0-100), 7 days to 5 years
keywords.relatedQueriesGET /v1/related-queries$0.03Google Trends top and rising related queries
keywords.interestByRegionGET /v1/interest-by-region$0.03Google Trends interest per region of a country

Keyword docs: https://keywords.duoleads.com/docs · OpenAPI: https://keywords.duoleads.com/openapi.json · Index: https://keywords.duoleads.com/llms.txt

Methods

Every method costs $0.05 per call. Each method's JSDoc gives the route and the parameters. client.call(path, params) calls any route, and client.callWithReceipt(path, params) also returns the settlement receipt.

MethodRouteWhat it does
iban.validate/v1/id/ibanIBAN validator: length, mod-97 check digits, bank/branch/account breakdown (89 countries)
iban.generate/v1/id/iban-buildIBAN generator: build an IBAN from country and BBAN or bank/branch/account, computing check digits
taxId.validate/v1/id/nationalVAT, tax ID and national ID validator: 23 countries, checksum only (VAT formats BE, DE, FR, IT, PL, AT, CH, IE)
isin.validate/v1/id/securityISIN validator plus CUSIP, SEDOL and FIGI check-digit validation; builds an ISIN from an NSIN
barcode.validate/v1/id/gs1GTIN barcode validator: EAN-13, UPC-A (GTIN-12), GTIN-8/14, GLN and SSCC check digits
timezone.convert/v1/time/zoneTimezone converter: instant to local time in an IANA time zone and back, with UTC offset and DST state
timezone.dstTransitions/v1/time/dstDST transitions: next daylight-saving time changes for an IANA time zone
businessDays.calculate/v1/time/business-daysBusiness days calculator: add or count working days with your weekend mask and holiday list
rrule.expand/v1/time/rruleRRULE expander: RFC 5545 recurrence rule to concrete occurrence dates
calendar.convert/v1/time/calendarCalendar converter: Gregorian to Hijri, Hebrew, Japanese era, Persian and more, plus Easter date

| text.similarity | /v1/text/similarity | String similarity: Levenshtein, Jaro-Winkler distance

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