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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 _indent_line(self, line, stripspace=''):
 """indent the given line according to the current indent level. stripspace is a string of space that will be truncated from the start of the line before indenting."""


        return re.sub(r"^%s" % stripspace, self.indentstring
                      * self.indent, line)