GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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## CAP package
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## Copyright 2015, Sebastian Gutsche, TU Kaiserslautern
## Sebastian Posur, RWTH Aachen
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#! @Chapter Serre Quotients Functors
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#! The operations in this chapter construct conversion functors between two
#! Serre quotients of different standards.
#! Please note that all the operations DO NOT CARE if the Serre quotients
#! are modeling the same category, they only care wether the categories are
#! based upon the same underlying honest category.
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#! @Section Functors
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#! @Description
#! Given two Serre quotients <A>A</A> and <A>B</A> of the same category <A>C</A> by equivalent functions, this operation
#! returns the conversion functor between the two categories. Please note that this function does not check the
#! quotients in any sense, i.e., wether the functions are equivalent.
#! @Arguments A,B
#! @Returns a functor
DeclareOperation( "SerreQuotientConversionFunctor",
[ IsCapCategory, IsCapCategory ] );