"Source: Text/Geometry/ModAbVar.text";
"Line: 2937";
"Date: Thu Sep 25 14:47:45 2025";
"Main: Fri Sep 26 14:29:19 2025";
// original file: Text/Geometry/ModAbVar.text, line: 2937
// Example: H148E56 ()
print "Example: H148E56";
ei := GetEchoInput();
SetEchoInput(true);
J := JZero(65);
A := Decomposition(J)[2]; A;
T := HeckeOperator(J,3);
Factorization(CharacteristicPolynomial(T));
Restriction(T,A); 
TonA := RestrictEndomorphism(T,A); TonA;
Factorization(CharacteristicPolynomial(TonA));
phi := T+2;
IsSurjective(phi);
assert not $1;
pi := SurjectivePart(phi);
IsSurjective(pi);
assert $1;
Codomain(pi);
SetEchoInput(ei);
