lexer and Python parser

Question

Inside the Python interpreter, which is a compiler that translates the source code into intermediate code and then interprets and executes the byte code.

But my questions before compiling and interpreting are:

If there is an unauthorized token in the code, at what stage does the syntax error related to the detection token occur? lexing or parsing

It is written in some places because the task of the lexer is to separate the signs of the language is meaningful and permissible, it gives an error at this stage.

In some places, hitting a meaningless token is considered unknown and is transferred to the next stage of parsing, where an error is taken.