let G3 be _Graph; :: thesis: for G4 being G3 -isomorphic _Graph
for G1 being addLoops of G3
for G2 being addLoops of G4 holds G2 is G1 -isomorphic

let G4 be G3 -isomorphic _Graph; :: thesis: for G1 being addLoops of G3
for G2 being addLoops of G4 holds G2 is G1 -isomorphic

let G1 be addLoops of G3; :: thesis: for G2 being addLoops of G4 holds G2 is G1 -isomorphic
let G2 be addLoops of G4; :: thesis: G2 is G1 -isomorphic
consider F0 being PGraphMapping of G3,G4 such that
A1: F0 is isomorphism by GLIB_010:def 23;
A2: dom ((F0 _V) | (the_Vertices_of G3)) = the_Vertices_of G3 by A1, GLIB_010:def 11;
rng ((F0 _V) | (the_Vertices_of G3)) = the_Vertices_of G4 by A1, GLIB_010:def 12;
then consider F being PGraphMapping of G1,G2 such that
( F _V = F0 _V & (F _E) | (dom (F0 _E)) = F0 _E ) and
( not F0 is empty implies not F is empty ) and
( F0 is total implies F is total ) and
( F0 is onto implies F is onto ) and
( F0 is one-to-one implies F is one-to-one ) and
( F0 is directed implies F is directed ) and
( F0 is weak_SG-embedding implies F is weak_SG-embedding ) and
A3: ( F0 is isomorphism implies F is isomorphism ) and
( F0 is Disomorphism implies F is Disomorphism ) by A1, A2, Th29;
thus G2 is G1 -isomorphic by A1, A3, GLIB_010:def 23; :: thesis: verum