After checked in Advanced -> Target variable in history functions ? and Export solutions as python. This variable does not appear in def solutions arg, only in return of functions. Example: def solution_15(imf_7, imf_45, imf_116, imf_83, imf_159, imf_311, imf_197, imf_2781, imf_463, imf_349, imf_2819, imf_268, imf_615, imf_420, imf_2852, imf_501, imf_235, imf_387, imf_572, imf_653, imf_767, imf_539, imf_724, imf_957, imf_805, imf_2743, imf_919, imf_691, imf_876, imf_843, imf_1028, imf_1109, imf_995, imf_1223, imf_1261, imf_1071, imf_88, here -> lack of l_num_set):
return moving_average(imf_83,2)-(ceil(moving_average(here ->we have l_num_set,2))-19)+(-1.7*imf_7).
