The generator matrix

 1  0  1  1  1  1  1  1  0  1  1  1  1  1  1  1  1  1  1  1
 0  1  1  3 5X+2  6 5X+4  5  1  0  6 5X+1  5 5X+2  5  3 5X+1 5X+2 5X+1 4X+2
 0  0 5X  0 5X  X 5X 6X 5X  X 3X  X 6X 6X  0 2X 6X  X 3X 3X
 0  0  0  X 4X 4X 3X 3X 5X 6X 3X 5X  X 6X 3X 6X 5X  0  X 6X

generates a code of length 20 over Z7[X]/(X^2) who´s minimum homogenous weight is 102.

Homogenous weight enumerator: w(x)=1x^0+42x^102+336x^103+456x^105+1176x^108+756x^109+2520x^110+456x^112+2058x^114+14112x^115+4536x^116+10416x^117+456x^119+12348x^121+42336x^122+9072x^123+15540x^124+456x^126+456x^133+120x^140

The gray image is a linear code over GF(7) with n=140, k=6 and d=102.
This code was found by Heurico 1.16 in 93.6 seconds.