GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
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##
## BasicFunctors.gd Graded Modules package
##
## Copyright 2007-2010, Mohamed Barakat, University of Kaiserslautern
## Markus Lange-Hegermann, RWTH Aachen
##
## Declaration stuff for basic functors of graded modules and maps.
##
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#
# global variables:
#
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## Cokernel
DeclareGlobalFunction( "_Functor_Cokernel_OnGradedModules" );
DeclareGlobalVariable( "functor_Cokernel_ForGradedModules" );
## ImageObject
DeclareGlobalFunction( "_Functor_ImageObject_OnGradedModules" );
DeclareGlobalVariable( "functor_ImageObject_ForGradedModules" );
## GradedHom
DeclareGlobalFunction( "_Functor_GradedHom_OnGradedModules" );
DeclareGlobalFunction( "_Functor_GradedHom_OnGradedMaps" );
DeclareGlobalVariable( "Functor_GradedHom_ForGradedModules" );
## TensorProduct
DeclareGlobalFunction( "_Functor_TensorProduct_OnGradedModules" );
DeclareGlobalFunction( "_Functor_TensorProduct_OnGradedMaps" );
DeclareGlobalVariable( "Functor_TensorProduct_ForGradedModules" );
## BaseChange
DeclareGlobalFunction( "_functor_BaseChange_OnGradedModules" );
DeclareGlobalVariable( "functor_BaseChange_ForGradedModules" );
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#
# global functions and operations:
#
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# basic operations:
DeclareOperation( "BaseChange_OnGradedModules",
[ IsHomalgRing, IsHomalgMap ] );
DeclareOperation( "GradedHom",
[ IsHomalgObject, IsHomalgObject ] );
DeclareOperation( "GradedExt",
[ IsInt, IsHomalgObject, IsHomalgObject ] );