<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def leading_whitespace_in_current_line(self):
 """ The leading whitespace in the left margin of the current line. """

        current_line = self.current_line
        length = len(current_line) - len(current_line.lstrip())
        return current_line[:length]