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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_start_of_line_position(self, after_whitespace=False):
 """ Relative position for the start of this line. """

        if after_whitespace:
            current_line = self.current_line
            return len(current_line) - len(current_line.lstrip()) - self.cursor_position_col
        else:
            return - len(self.current_line_before_cursor)