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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 addcomment(self, invoice_increment_id, comment=None, email=False, include_comment=False):
 """ Add comment to invoice or change its state :param invoice_increment_id: Invoice ID """

        if comment is None:
            comment = ""
        return bool(
            self.call(
                'sales_order_invoice.addComment',
                [invoice_increment_id, comment, email, include_comment]
            )
        )