How to use the autopep8.ReformattedLines._Space function in autopep8

def add_comment(self, item):
        num_spaces = 2
        if len(self._lines) > 1:
            if isinstance(self._lines[-1], self._Space):
                num_spaces -= 1
            if len(self._lines) > 2:
                if isinstance(self._lines[-2], self._Space):
                    num_spaces -= 1

        while num_spaces > 0:
            self._lines.append(self._Space())
            num_spaces -= 1
        self._lines.append(item)

return

        if not self._prev_item:
            return

        item_text = unicode(item)
        prev_text = unicode(self._prev_item)

        # Prefer a space around a '.' in an import statement, and between the
        # 'import' and '('.
        if (
            (item_text == '.' and prev_text == 'from') or
            (item_text == 'import' and prev_text == '.') or
            (item_text == '(' and prev_text == 'import')
        ):
            self._lines.append(self._Space())

# Put a space after a colon or comma.
              prev_text[-1] in ':,' or

              # Put space around '=' if asked to.
              (equal and prev_text == '=') or

              # Put spaces around non-unary arithmetic operators.
              ((self._prev_prev_item and
                (prev_text not in '+-' and
                 (self._prev_prev_item.is_name or
                  self._prev_prev_item.is_number or
                  self._prev_prev_item.is_string)) and
                prev_text in ('+', '-', '%', '*', '/', '//', '**', 'in')))))
        ):
            self._lines.append(self._Space())