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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 get(issue_id, issue_type_id):
 """Return issue by ID Args: issue_id (str):
 Unique Issue identifier issue_type_id (str):
 Type of issue to get Returns: :obj:`Issue`: Returns Issue object if found, else None """

        return db.Issue.find_one(
            Issue.issue_id == issue_id,
            Issue.issue_type_id == issue_type_id
        )