why symbol r'^ used in python code example

Example 1: python tab character

Escape Sequence       Meaning
\t                    Tab
\\                    Inserts a back slash (\)
\'                    Inserts a single quote (')
\"                    Inserts a double quote (")
\n                    Inserts a ASCII Linefeed (a new line)

Example 2: python escape characters

\'	Single Quote	
\\	Backslash
newline = '\n'