The meaning of R in the Django URL

For example:

Urlpatterns = Patterns ("',    # ...    (R ' ^time/plus/\d+/$ ', Hours_ahead),    # ...)

The beginning letter "R" of the regular expression string. It tells Python that this is an original string and does not need to handle the backslash (escape character) inside. In a normal Python string, backslashes are used to escape special characters. For example, N escapes into a newline character. When you use R to mark it as an original string, Python no longer sees the backslash as an escape character. In other words, "n" is a two string: "" and "N". Because backslashes have conflicts in Python code and regular expressions, it is recommended that you use the original string when you define a regular expression in Python.  

The meaning of R in the Django URL