What is the origin of /prog/snake?

%!PS-Adobe-3.0 EPSF-3.0
% THE /prog/SNAKE, NOW IN RESOLUTION-INDEPENDENT FORMAT!
%%BoundingBox: 49 202 554 618
%!PS-Adobe-3.0 EPSF-3.0
%%BoundingBox: 49 202 554 618
/b {bind def} bind def
/c {curveto} b
/i {fill} b
/l {lineto} b
/m {moveto} b
/n {newpath} b
/r {setrgbcolor} b
/s {closepath} b
/v {currentpoint 6 2 roll curveto} b
/y {2 copy c} b

0 setlinecap 0 setlinejoin 3 setlinewidth 1 setmiterlimit []0 setdash
% snake
n
49.75 299.3291 m
51.3418 296.4854 54.208 294.124 57.083 292.374 c
62.8398 288.8701 69.1499 286.2617 75.3457 283.6426 c
80.4258 281.4941 85.6665 280.0488 90.998 278.6758 c
95.8726 277.4219 100.5928 276.4355 105.6338 276.2402 c
111.9551 275.9951 131.543 276.0938 135.0625 276.125 c
144.104 276.208 146.6514 279.0107 153.458 283.249 c
160.083 287.374 167.8838 292.085 175.1665 293.166 c
180.936 294.0234 189.333 294.5 201 293.833 c
205.334 293.585 210.1904 292.9424 214.5 292.333 c
218.1743 291.8135 222.8687 290.8008 226.333 289.624 c
233.688 287.125 240.4219 283.1396 246.0322 277.7676 c
247.75 276.123 249.3525 274.3623 250.833 272.5 c
255.0801 267.1572 259.354 261.6475 262.3765 255.4932 c
263.6763 252.8477 264.5425 250.1582 264.9453 247.2402 c
265.2207 245.2461 265.7939 242.6084 265.208 240.624 c
264.666 238.7881 261.5874 236.6484 260 235.833 c
256.3076 233.9375 255 232.833 250.5 232.2734 c
245.4355 231.6436 240.2808 231.1611 235.1733 231.4092 c
230.8643 231.6191 226.2896 232.1855 222.1045 233.2363 c
219.7886 233.8174 217.541 234.7256 215.4927 235.9541 c
213.4922 237.1533 211.875 238.3125 209.708 239.874 c
211.375 236.5625 213.354 230.6738 216.458 228.124 c
218.2822 226.625 221.0059 225.5654 223.2451 224.9043 c
228.6265 223.3154 234.709 222.793 240.3096 222.7725 c
241.9971 222.7666 243.6909 222.8945 245.3462 223.2344 c
249.9248 224.1738 253.8018 226.8438 257.7769 229.1494 c
258.6597 229.6611 259.5542 230.1504 260.458 230.624 c
258.1025 224.7129 257.208 223.249 v
255.833 220.999 253.333 216.874 248.583 212.874 c
244.2358 209.2139 238.5078 206.0488 232.9878 204.6055 c
228.6025 203.459 223.8525 203.3154 219.3438 203.041 c
213.249 202.6719 207.0391 202.1934 200.958 202.999 c
192.458 204.124 188.2471 204.8838 181.083 206.874 c
176.2847 208.207 171.4907 209.5039 166.8149 211.2344 c
164.4028 212.127 162.0103 213.0977 159.708 214.249 c
151.1685 218.5186 149.3032 219.999 147.583 219.999 c
139.6963 219.999 122.458 219.999 y
90 220 84.9951 219.9824 v
80.875 219.9678 76.9854 220.2051 73.0684 220.8154 c
70.292 221.248 67.1167 222.2734 64.458 223.124 c
61.333 224.124 57.6816 225.7334 53.7813 227.6875 c
52.5063 228.3262 51.2813 228.7813 49.75 229.5791 c
s i
% snake's eyes and nostrils
1 1 1 r
n
220.75 270.25 m
220.75 265.6934 217.0562 262 212.5 262 c
207.9438 262 204.25 265.6934 204.25 270.25 c
204.25 274.8066 207.9438 278.5 212.5 278.5 c
217.0562 278.5 220.75 274.8066 220.75 270.25 c
s
257.5 247.375 m
257.5 245.9248 256.3247 244.75 254.875 244.75 c
253.4253 244.75 252.25 245.9248 252.25 247.375 c
252.25 248.8252 253.4253 250 254.875 250 c
256.3247 250 257.5 248.8252 257.5 247.375 c
s i
0 0 0 r
n
215.25 273.5 m
215.25 272.1191 214.1309 271 212.75 271 c
211.3691 271 210.25 272.1191 210.25 273.5 c
210.25 274.8809 211.3691 276 212.75 276 c
214.1309 276 215.25 274.8809 215.25 273.5 c
s i

an@us:~/cudder$ ls
action/ talk/
an@us:~/cudder$ ls action/
an@us:~/cudder$ Edited on 19/09/2019 12:31.

>>4↵
an@us:~/cudder$ ls -l
an@us:~/cudder$ ls
action/ talk/
an@us:~/cudder$ ls -l action/
an@us:~/cudder$ ls action/
an@us:~/cudder$