def markInputline( self, markerString = ">!<" ):
        """Extracts the exception line from the input string, and marks
           the location of the exception with a special symbol.
        """
        line_str = self.line
        line_column = self.column - 1
        if markerString:
            line_str = "".join((line_str[:line_column],
                                markerString, line_str[line_column:]))
        return line_str.strip()
Extracts the exception line from the input string, and marks
           the location of the exception with a special symbol.
        
src/pkg_resources/_vendor/pyparsing.py