Create a new issue.
        :param title: the title of the issue
        :param content: the description of the issue
        :param priority: the priority of the ticket
        :param milestone: the milestone of the ticket
        :param tags: comma sperated list of tag for the ticket
        :param assignee: the assignee of the ticket
        :param private: whether create this issue as private
        :return:

def create_issue(self, title, content, priority=None,
                     milestone=None, tags=None, assignee=None,
                     private=None):
        """
        Create a new issue.
        :param title: the title of the issue
        :param content: the description of the issue
        :param priority: the priority of the ticket
        :param milestone: the milestone of the ticket
        :param tags: comma sperated list of tag for the ticket
        :param assignee: the assignee of the ticket
        :param private: whether create this issue as private
        :return:
        """
        request_url = "{}new_issue".format(self.create_basic_url())

        payload = {'title': title, 'issue_content': content}

        if priority is not None:
            payload['priority'] = priority
        if milestone is not None:
            payload['milestone'] = milestone
        if tags is not None:
            payload['tag'] = tags
        if assignee is not None:
            payload['assignee'] = assignee
        if private is not None:
            payload['private'] = private

        return_value = self._call_api(request_url,
                                      method='POST', data=payload)

        LOG.debug(return_value)