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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 getResultsInterpretationByDepartment(self, department=None):
 """Returns the results interpretation for this Analysis Request and department. If department not set, returns the results interpretation tagged as 'General'. :returns: a dict with the following keys: {'uid': <department_uid> or 'general', 'richtext': <text/plain>} """

        uid = department.UID() if department else 'general'
        rows = self.Schema()['ResultsInterpretationDepts'].get(self)
        row = [row for row in rows if row.get('uid') == uid]
        if len(row) > 0:
            row = row[0]
        elif uid == 'general' \
                and hasattr(self, 'getResultsInterpretation') \
                and self.getResultsInterpretation():
            row = {'uid': uid, 'richtext': self.getResultsInterpretation()}
        else:
            row = {'uid': uid, 'richtext': ''}
        return row