The following code will cause a syntax error when run

x = "#"
print(x)

I guess the interpreter thinks the # string is the start of a comment.

Why did I need this? I am trying to send the GRBL command "$#" to the GRBL stepmotor module. (which is one of the commands it accepts).

Workaround

x=b'\x23'.decode()
grbl.g_code('$'+x)