Sumlock ANITA calculator - AbsoluteAstronomy.com

The ANITA Mark VII and ANITA Mark VIII calculator

Calculator

An electronic calculator is a small, portable, usually inexpensive electronic device used to perform the basic operations of arithmetic. Modern calculators are more portable than most computers, though most PDAs are comparable in size to handheld calculators.The first solid-state electronic...

s were launched simultaneously in late 1961 as the world's first all-electronic

Electronics

Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...

desktop calculators. Designed and built by the Bell Punch Co

Bell Punch

The Bell Punch Company was a British company manufacturing a variety of business machines, most notably several generations of public transport ticket machines and the worlds first desktop electronic calculator, the Sumlock ANITA.-History:...

. in Britain

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, and marketed through its Sumlock Comptometer division, they used vacuum tube

Vacuum tube

In electronics, a vacuum tube, electron tube , or thermionic valve , reduced to simply "tube" or "valve" in everyday parlance, is a device that relies on the flow of electric current through a vacuum...

s and cold-cathode switching tubes in their logic circuits and nixie tube

Nixie tube

A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

s for their numerical displays.

They were the first of a series of desktop and hand-held electronic calculators that the company was to develop and sell under the ANITA name into the mid-1970s.

History of ANITA calculators

The acronym 'ANITA' was officially proclaimed to be derived from, variously, A New Inspiration To Arithmetic, or A New Inspiration To Accounting, though there have been rumours that this was also the name of the designer's wife.

The Bell Punch Company (named after its first product, a ticket punch with a bell used by tram

Tram

A tram is a passenger rail vehicle which runs on tracks along public urban streets and also sometimes on separate rights of way. It may also run between cities and/or towns , and/or partially grade separated even in the cities...

and bus

Bus

A bus is a road vehicle designed to carry passengers. Buses can have a capacity as high as 300 passengers. The most common type of bus is the single-decker bus, with larger loads carried by double-decker buses and articulated buses, and smaller loads carried by midibuses and minibuses; coaches are...

conductors) had been producing a very successful range of key-driven mechanical calculators of the Comptometer

Comptometer

The comptometer was the first commercially successful key-driven mechanical calculator, patented in the USA by Dorr E. Felt in 1887.A key-driven calculator is extremely fast because each key adds or subtracts its value to the accumulator as soon as it is pressed and a skilled operator can enter all...

type under the names "Plus" and "Sumlock", since the 1930s. In 1956 the young graduate Norbert Kitz (also known as Norman Kitz), who had worked on the early British Pilot ACE

Pilot ACE

The Pilot ACE was one of the first computers built in the United Kingdom, at the National Physical Laboratory in the early 1950s.It was a preliminary version of the full ACE, which had been designed by Alan Turing. After Turing left NPL , James H...

computer project, had a chance meeting with some of the directors of Control Systems Ltd., of which the Bell Punch Company was then a subsidiary. Some years earlier, while researching the introduction to his dissertation, he was looking at the mechanical calculators in the Science Museum

Science museum

A science museum or a science centre is a museum devoted primarily to science. Older science museums tended to concentrate on static displays of objects related to natural history, paleontology, geology, industry and industrial machinery, etc. Modern trends in museology have broadened the range of...

, London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

, United Kingdom

United Kingdom

, and had realised that the future of calculators lay in electronics. Unfortunately, the major mechanical calculator manufacturers were far away in the U.S.A. and Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, and Kitz's idea lay dormant until he raised it at that meeting. The directors were very forward looking and were impressed by Kitz and his idea. They decided to open an Electronics Development Department, and took on Kitz as the leader of a project to develop an electronic version of the company's mechanical calculators. To help confidentiality the project was given the code-name ANITA.

Since the company had production lines capable of manufacturing precision mechanical parts by the thousand, the first experimental models were mechanical and electronic hybrids. However, these proved impractical and a purely electronic design was pursued.

Being the first in the field there were several major technical areas that required considerable development:

Development of the electronic circuits for the four arithmetic functions: add, subtract, multiply, divide.
Development of an electronic circuit which could store numbers being used in the calculation without taking up a lot of space and requiring a lot of power.
Produce a suitable keyboard to enter the numbers of a calculation. This had to have a long life and also give good electrical reliability.
To develop a suitable numerical output to display the results.

However, the main constraint was to be the cost of the calculator. The cheapest electronic computer then cost approximately £50,000 (GBP, about US$140,000), but to be competitive with mechanical calculators the target selling price of the electronic calculator was in the range £350 to £400 (US$980 to 1120).

The first all-electronic prototype was demonstrated to the board of the company in December 1958. It is interesting to note that this prototype was later donated by the company to the Science Museum

Science Museum (London)

The Science Museum is one of the three major museums on Exhibition Road, South Kensington, London in the Royal Borough of Kensington and Chelsea. It is part of the National Museum of Science and Industry. The museum is a major London tourist attraction....

in London

London

, where Kitz had originally had the idea for the electronic calculator. It has been on display surrounded by the mechanical calculators that it was to make obsolete. There then followed several years of great effort in finding electronic and mechanical components suitable for production, testing them for suitability, and where necessary producing them within the company or finding someone to produce them to their specification.

The great culmination of all the effort was revealed in October 1961, when the world's first all-electronic desktop calculators were launched. These were the ANITA Mk VIII at the Business Efficiency Exhibition in London

London

, United Kingdom

United Kingdom

, from 2nd. to 11th. October, and the ANITA Mk VII at the Hamburg Business Equipment Fair, Germany

Germany

, from 10th. to 13th. October.

Since transistor

Transistor

A transistor is a semiconductor device used to amplify and switch electronic signals and power. It is composed of a semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current...

technology was still in its infancy, these machines used vacuum tube

Vacuum tube

s, cold-cathode tubes, and Dekatron

Dekatron

In electronics, a Dekatron is a gas-filled decade counting tube. Dekatrons were used in computers, calculators and other counting-related products during the 1950s and 1960s...

s in their circuits, and cold-cathode Nixie tube

Nixie tube

s for their displays. This technology was fairly robust and cost effective; the Dekatron counter tube being the equivalent of an integrated circuit

Integrated circuit

An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

counter

Counter

In digital logic and computing, a counter is a device which stores the number of times a particular event or process has occurred, often in relationship to a clock signal.- Electronic counters :...

. The ANITA Mk VII was marketed in continental Europe while the ANITA Mk VIII was marketed in Britain and the rest of the world, both for delivery from early 1962. The Mk VII was a slightly earlier design with a more complicated mode of multiplication and was soon dropped in favour of the simpler Mark VIII version. The logic circuits, although digital, were based on decimal notation rather than binary; as Kitz himself stated at a symposium "no binary stunts here!". Similar to the Comptometer

Comptometer

calculating machines of the time, the ANITA had a full keyboard, a feature that was unique to it and the later Sharp

Sharp Corporation

is a Japanese multinational corporation that designs and manufactures electronic products. Headquartered in Abeno-ku, Osaka, Japan, Sharp employs more than 55,580 people worldwide as of June 2011. The company was founded in September 1912 and takes its name from one of its founder's first...

CS-10A among electronic calculators. Being silent and very quick in operation, and the only electronic desktop calculator available, the ANITA sold well, reaching nearly 10,000 units per year by 1964.

1961 was a doubly notable year for the Bell Punch Company since it then also amalgamated its calculator division with the British operation of Comptometer Corporation of Chicago, U.S.A. (formerly the Felt & Tarrant Manufacturing Co.), to form Sumlock Comptometer Ltd. It thus gained the right to use the name "Comptometer
Comptometer
The comptometer was the first commercially successful key-driven mechanical calculator, patented in the USA by Dorr E. Felt in 1887.A key-driven calculator is extremely fast because each key adds or subtracts its value to the accumulator as soon as it is pressed and a skilled operator can enter all...

" and even manufactured mechanical calculators to be sold by Comptometer Corporation in the U.S.A.

Development and some manufacture of the ANITA calculators took place at the Bell Punch Company's headquarters in Uxbridge

Uxbridge

Uxbridge is a large town located in north west London, England and is the administrative headquarters of the London Borough of Hillingdon. It forms part of the ceremonial county of Greater London. It is located west-northwest of Charing Cross and is one of the major metropolitan centres...

, about 15 miles (24 km) to the west of London

London

, United Kingdom

United Kingdom

. However, the main production facility was in Portsmouth

Portsmouth

Portsmouth is the second largest city in the ceremonial county of Hampshire on the south coast of England. Portsmouth is notable for being the United Kingdom's only island city; it is located mainly on Portsea Island...

, on the south coast, where the company expanded the original site there, opened in 1952 to produce mechanical calculator parts, by acquiring additional buildings. For production of the thousands of circuit boards the company invested in the then new technology of wave soldering

Wave soldering

Wave soldering is a large-scale soldering process by which electronic components are soldered to a printed circuit board to form an electronic assembly. The name is derived from the use of waves of molten solder to attach metal components to the PCB...

.

With the appearance of the ANITA calculators, other calculator manufacturers pressed on with designs for electronic models. In late 1963 and 1964 competition finally arrived with the launch of all-transistor

Transistor

models such as the Friden EC-130, IME 84, and Sharp CS-10A. Initially the competing electronic calculators were no cheaper nor smaller than the ANITA, but Bell Punch responded by opening a new research and development building on its Uxbridge site, and electronics research was increased for the calculators and the other Bell Punch products.

The ANITA name continued to be used for the series of models of desktop calculators that followed, which gradually moved to transistor

Transistor

and integrated circuit

Integrated circuit

technology, and from the early 1970s, the hand-held models.

In 1966 the calculator manufacturing operation of the Bell Punch Company was formed into a separate company, called Sumlock-Anita Electronics, and continued to manufacture both the mechanical and electronic calculators, still marketed by its Sumlock Comptometer division.

There was a major development in 1973 when the Sumlock Anita Electronics division was bought by its main supplier of integrated circuits, Rockwell International

Rockwell International

Rockwell International was a major American manufacturing conglomerate in the latter half of the 20th century, involved in aircraft, the space industry, both defense-oriented and commercial electronics, automotive and truck components, printing presses, valves and meters, and industrial automation....

of the U.S.A. The remainder of the Bell Punch Co. continued manufacturing and selling its other products, such as taximeters.

In 1976 Rockwell decided to exit the calculator market, by which time cheap calculators had markedly reduced the profitability of the industry. Sumlock Anita Electronics was closed down and the ANITA name was sold to a marketing company and soon disappeared. The rest of the Bell Punch Company, which was completely independent of Rockwell, continued in business to about 1986 when it was closed down.

Further information about the early ANITA calculators

The first of the ANITA models was called the Mk VII (i.e. Mark VII) because the development of the mechanism of the Sumlock mechanical calculators made by the company had already gone through design numbers Mk I to Mk VI. So the next number in the series was used for the first electronic design.
The moulded plastic casing of the first ANITA calculators was particularly complicated for the time, and required development of new techniques by the moulding company. Originally moulded in ABS
Acrylonitrile butadiene styrene
Acrylonitrile butadiene styrene is a common thermoplastic. Its melting point is approximately 105 °C ....

the material was later changed to polycarbonate
Polycarbonate
PolycarbonatePhysical PropertiesDensity 1.20–1.22 g/cm3Abbe number 34.0Refractive index 1.584–1.586FlammabilityV0-V2Limiting oxygen index25–27%Water absorption – Equilibrium0.16–0.35%Water absorption – over 24 hours0.1%...

for improved fire resistance.
Operators converting from mechanical machines to the new electronic ANITA calculators often complained initially that the key stroke was too light and did not give the feel of the mechanical machine. Also, they missed the noise of the mechanism which indicated that the calculation was taking place and went quiet when the calculation was completed.
An article of 1965 on cold cathode tubes from Mullard Ltd. (a British manufacturer of these devices, which also produced a prototype calculator using them) gives an insight into why they were used in these calculators at the time - "... They are an accountant's dream; a typical modern [cold cathode] tube has a life expectancy several thousand times better than the conventional thermionic tube, although they employ voltages of the same order. They are much cheaper than either semiconductor devices or vacuum tubes; they do not require costly materials with a high degree of purity in their manufacture, nor do they need transformers or cooling systems to operate. The tubes require no warm-up period and they can take severe overload."

Desktop models

ANITA Mk VII - 1961, cold-cathode tube logic, full keyboard, 12-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display.
ANITA Mk VIII (aka Mk 8) - 1961, cold-cathode tube logic, full keyboard, 12-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display.
ANITA Mk 9 - 1964, cold-cathode tube logic, full keyboard, 12-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, capable of chain multiplication.
ANITA Mk 10 - 1965, cold-cathode tube logic, full keyboard, 12-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, can display in Decimal or the pre-decimalisation Pound sterling
Pound sterling
The pound sterling , commonly called the pound, is the official currency of the United Kingdom, its Crown Dependencies and the British Overseas Territories of South Georgia and the South Sandwich Islands, British Antarctic Territory and Tristan da Cunha. It is subdivided into 100 pence...

Currency mode.
ANITA Mk 11 - 1968, hybrid cold-cathode tube and transistor logic, 10-key keyboard, 9-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, low cost.
ANITA Mk12 - 1966, hybrid cold-cathode tube and transistor logic, 10-key keyboard, 12-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display.

ANITA 410P - details not known.
ANITA 500P - details not known.
ANITA 1000 - 1969, IC & transistor logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display.
ANITA 1010 - 1969, IC & transistor logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, %.
ANITA 1011 - 1969, IC & transistor logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, memory.
ANITA 1011P - 1971, IC & transistor logic, 10-key keyboard, printer, memory.
ANITA 1020 - 1970, IC & transistor logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, square root.
ANITA 1021 - 1970, IC & transistor logic, 10-key keyboard, memory, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, memory, square root.

ANITA 1000 LSI - 1971, IC logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display.
ANITA 1000B LSI - c1971, IC logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, AC & rechargeable batteries.
ANITA 1011 LSI - 1971, IC logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, %, memory.
ANITA 1011B LSI - 1971, IC logic, 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, %, memory, AC & rechargeable batteries.
ANITA 1011P - c1971, IC logic (?), 10-key keyboard, printer, %, memory.
ANITA 1021 LSI - details unknown.
ANITA 1041 - details unknown.
ANITA 1211 LSI (aka 1211D) - IC logic, 10-key keyboard, 12-digit "Panaplex" display, %.
ANITA 1211P - 1973, IC logic (?), 10-key keyboard, printer.
ANITA 1212D - 1972, IC logic (?), 10-key keyboard, 10-digit "Nixie"
Nixie tube
A nixie tube is an electronic device for displaying numerals or other information. The glass tube contains a wire-mesh anode and multiple cathodes. In most tubes, the cathodes are shaped like numerals. Applying power to one cathode surrounds it with an orange glow discharge...

-type tube display, 2 memories.
ANITA 1212P - date unknown, IC logic (?), 10-key keyboard, printer.
ANITA 1233D - 1972, IC logic (?), 10-key keyboard, multiple memories.
ANITA 1233P - 1973, IC logic (?), 10-key keyboard, printer, multiple memories.

Rockwell-ANITA 811 SL - 1974, IC logic, 10-key keyboard, 8-digit "Panaplex II" display, %, memory.
Rockwell-ANITA 1041 - 1975, IC logic, 10-key keyboard, 16-digit "Panaplex II" (10 digits mantissa, 2 digits exponent), scientific functions, memory.
Rockwell-ANITA 1211 - date unknown, IC logic, 10-key keyboard, 12-digit "Panaplex II" display, %, memory.
Rockwell-ANITA 1211 SL - 1974, IC logic, 10-key keyboard, 12-digit "Panaplex II" display, %, memory.
Rockwell-ANITA 1211P - 1973, IC logic, 10-key keyboard, printer.
Rockwell-ANITA 1216 - c1973, IC logic, 10-key keyboard, 12-digit "Panaplex"-type display, %, memory, made in U.S.A.
Rockwell-ANITA 1432 - details unknown.

Hand-held models

ANITA 810 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display.
ANITA 811 - 1972, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, %, memory. The first Anita hand-held calculator.
ANITA 831 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, %, memory, square root.
ANITA 841 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, Scientific.
ANITA 851 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, metric conversion.
ANITA 861 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, Financial.
ANITA 8041 - date unknown, 8-digit green Vacuum fluorescent display
Vacuum fluorescent display
A vacuum fluorescent display is a display device used commonly on consumer-electronics equipment such as video cassette recorders, car radios, and microwave ovens. Invented in Japan in 1967, the displays became common on calculators and other consumer electronics devices...

, scientific, similar to ANITA 841, made in Yugoslavia for Fi-cord International, Didsbury, Manchester, England.
Triumph-Adler 81 - c1972, similar to the ANITA 811. Made by Sumlock-Anita for Triumph-Adler and sold under both the "Triumph" and "Adler" labels.

Rockwell-ANITA 102 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, assembled in Mexico.
Rockwell-ANITA 201 - date unknown, 8-digit red LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....

display, %, memory, assembled in Mexico.
Rockwell-ANITA 202/SR - date unknown, 8-digit green Vacuum fluorescent display
Vacuum fluorescent display
A vacuum fluorescent display is a display device used commonly on consumer-electronics equipment such as video cassette recorders, car radios, and microwave ovens. Invented in Japan in 1967, the displays became common on calculators and other consumer electronics devices...

, scientific, assembled in Mexico (?).

Sumlock-Anita Electronics also assembled in Britain some of the Rockwell hand-held calculators, including Rockwell models 8R, 10R, 18R, 20R, 21R, 30R, 31R.

The "Panaplex" is a gas-discharge display, using 7 segments to represent each number, within a thin glass "sandwich". The numerals glow amber.

Note that this list of calculator models may not be complete.

Patents

GB patent 868,753 – Improvements in or relating to Calculating Machines – Norbert Kitz, Robert Milburn, Christopher Webb: Bell Punch Company Ltd., 1961 (first application Sept. 6, 1956, filed Sept. 6, 1957), - Electronically controlled key operated office desk type calculating machine capable of addition, subtraction, multiplication, and division. - Key controlled decimal electronic calculating machine – Norbert Kitz: Bell Punch Company Ltd., 1966 (filed Dec. 29, 1961), - Electromechanical and "space discharge type" electronic calculating machine capable of addition, subtraction, multiplication, and division.

External links

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