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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 create( self, order_increment_id, creditmemo_data=None, comment=None, email=False, include_comment=False, refund_to_store_credit_amount=None):
 """ Create new credit_memo for order :param order_increment_id: Order Increment ID :type order_increment_id: str :param creditmemo_data: Sales order credit memo data (optional) :type creditmemo_data: associative array as dict { 'qtys': [ { 'order_item_id': str, # Order item ID to be refunded 'qty': int # Items quantity to be refunded }, ], 'shipping_amount': float # refund shipping amount (optional) 'adjustment_positive': float # adjustment refund amount (optional) 'adjustment_negative': float # adjustment fee amount (optional) } :param comment: Credit memo Comment :type comment: str :param email: send e-mail flag (optional) :type email: bool :param include_comment: include comment in e-mail flag (optional) :type include_comment: bool :param refund_to_store_credit_amount: amount to refund to store credit :type refund_to_store_credit_amount: float :return str, increment id of credit memo created """

        if comment is None:
            comment = ''
        return self.call(
            'sales_order_creditmemo.create', [
                order_increment_id, creditmemo_data, comment, email, include_comment, refund_to_store_credit_amount
            ]
        )