I found the error, the correct d should be:
d = fdesign.bandpass('Fst1,Fp1,Fp2,Fst2,Ast1,Ap,Ast2',38e3,f_p,f_s,53e3,r_s,r_p,r_s,140e3);
Okay, so now that it compiled, I've ran into some concerns. For one thing, how can I tell if this is right and if it meets the problem description? I know it...