current instructions are
Allowed input file syntax
C FLOAT (C is a char, FLOAT is a float)
Combinations
F distance (move turtle forward by 'distance', print line if pencil is down)
T angle (turn turtle by 'angle' (positive angle counterclockwise))
U (move pencil up)
D (move pencil down)
[ repetition (start of loop repeat until ']' 'repetition' times)
] (end of loop)
{ (remember coordinates and angle)
} (goto remembered coordinates and angle)
WARNING it is not allowed to cross [] and {} e.g {[}] or [{]}