<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def issue(self, invoice_id, **kwargs):
 """" Issues an invoice in draft state Args: invoice_id : Id for delete the invoice Returns: Its response is the invoice entity, similar to create/update API response. Its status now would be issued. """

        url = "{}/{}/issue".format(self.base_url, invoice_id)
        return self.post_url(url, {}, **kwargs)