Using in-line variable substitution in Calculate Field Python within ModelBuilder gives a correct but potentially misleading error message which gives the appearance the tool fails but it works as intended.

Additional Information

Workaround

Ignore the error message but if there is other things wrong with the calculation this is to be overlooked.

Note: %-% is not valid Python, the validator correctly throws an error. Writing proper Python takes care of this. Enclose the variable needed to replace in a string.

Steps to Reproduce