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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_issue(self, data, params=None):
 """Creates an issue or a sub-task from a JSON representation. You can provide two parameters in request's body: update or fields. The fields, that can be set on an issue create operation, can be determined using the /rest/api/2/issue/createmeta resource. If a particular field is not configured to appear on the issue's Create screen, then it will not be returned in the createmeta response. A field validation error will occur if such field is submitted in request. Creating a sub-task is similar to creating an issue with the following differences: issueType field must be set to a sub-task issue type (use /issue/createmeta to find sub-task issue types), and You must provide a parent field with the ID or key of the parent issue. Args: data: params: Returns: """

        return self._post(self.API_URL + 'issue', data=data, params=params)