what is spell Fields

in the spell chess variant FEN there is spellFields what is it

here is the FEN

R-0,1,0,1-1,1,1,1-1,1,1,1-0,0,0,0-0-{'pawnBaseRank':5,'wb':true,'dim':'8x8','spells': ()'jump_0x2,freeze_0x5','','jump_0x2,freeze_0x5',''),'spellFields': ())}-
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,yR,yN,yB,yQ,yK,yB,yN,yR,x,x,x/
x,x,x,yP,yP,yP,yP,yP,yP,yP,yP,x,x,x/
x,x,x,8,x,x,x/
x,x,x,8,x,x,x/
x,x,x,8,x,x,x/
x,x,x,8,x,x,x/
x,x,x,rP,rP,rP,rP,rP,rP,rP,rP,x,x,x/
x,x,x,rR,rN,rB,rQ,rK,rB,rN,rR,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x

please

awesome

Hj

It might be the places you can spell

R-0,0,0,0-1,1,1,1-1,1,1,1-0,0,0,0-0-{'pawnBaseRank':5,'dim':'6x6','spells''jump_0x2,freeze_0x2','','jump_0x2,freeze_0x2',''),'spellFields')}-
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,yA,yF,0u,0u,bP,bA,x,x,x,x/
x,x,x,x,yP,yP,0u,0u,bP,bF,x,x,x,x/
x,x,x,x,6,x,x,x,x/
x,x,x,x,6,x,x,x,x/
x,x,x,x,rF,rP,0u,0u,gP,gP,x,x,x,x/
x,x,x,x,rA,rP,0u,0u,gF,gA,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x/
x,x,x,x,x,x,x,x,x,x,x,x,x,x

edited moderator AndrewSmith 

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