When you meet this error, it means there are some problem with your Unicode escaping.
For example, you are using a path like:
\ in python is an escape, python won't treat
C:\path\to\your\file as a path.
or you will get an error like:
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 16-17: truncated \UXXXXXXXX escape
there are at least two solutions for this problem
now, python will know its a path.
this method is quite simple, and you may see many people have chosen this way:
r prefix will make python treat the following string as a raw, un-escaped string. The escape character is backslash, that is why a normal string will not work as a Windows path string.