Quoting backslashes in Python string literals - Stack Overflow.
If the user actually inputted the data, as you say, then it should work. If however, you are testing it with a string literal, then it won't work. The string literal will treat the backslash as a escape character, and the number following defines the ASCII of the specified character. So, in that case, there isn't any backslash in the string. Henry.
out of 5.