GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
gap> START_TEST("HAP library"); gap> Read(Concatenation(dir,"bing.txt")); gap> BingsHouse; Regular CW-complex of dimension 2 gap> BingsModifiedHouse; Regular CW-complex of dimension 3 gap> Size(BingsHouse); 309 gap> Size(BingsModifiedHouse); 311 gap> Size(ContractedComplex(BingsModifiedHouse)); 1 gap> Size(ContractedComplex(BingsHouse)); 309 gap> STOP_TEST( "tst.tst", 1000 );