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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 issue_types(self):
 """Get a list of issue type Resources from the server. :rtype: List[IssueType] """

        r_json = self._get_json('issuetype')
        issue_types = [IssueType(
            self._options, self._session, raw_type_json) for raw_type_json in r_json]
        return issue_types