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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_staff(self, gradebook_id, simple=False):
 """Get staff list for gradebook. Get staff list for the gradebook specified. Optionally, return a less detailed list by specifying ``simple = True``. If simple=True, return a list of dictionaries, one dictionary for each member. The dictionary contains a member's ``email``, ``displayName``, and ``role``. Members with multiple roles will appear in the list once for each role. Args: gradebook_id (str):
 unique identifier for gradebook, i.e. ``2314`` simple (bool):
 Return a staff list with less detail. Default is ``False``. Returns: An example return value is: .. code-block:: python { u'data': { u'COURSE_ADMIN': [ { u'accountEmail': u'benfranklin@mit.edu', u'displayName': u'Benjamin Franklin', u'editable': False, u'email': u'benfranklin@mit.edu', u'givenName': u'Benjamin', u'middleName': None, u'mitId': u'921344431', u'nickName': u'Benjamin', u'personId': 10710616, u'sortableName': u'Franklin, Benjamin', u'surname': u'Franklin', u'year': None }, ], u'COURSE_PROF': [ { u'accountEmail': u'dduck@mit.edu', u'displayName': u'Donald Duck', u'editable': False, u'email': u'dduck@mit.edu', u'givenName': u'Donald', u'middleName': None, u'mitId': u'916144889', u'nickName': u'Donald', u'personId': 8117160, u'sortableName': u'Duck, Donald', u'surname': u'Duck', u'year': None }, ], u'COURSE_TA': [ { u'accountEmail': u'hduck@mit.edu', u'displayName': u'Huey Duck', u'editable': False, u'email': u'hduck@mit.edu', u'givenName': u'Huey', u'middleName': None, u'mitId': u'920445024', u'nickName': u'Huey', u'personId': 1299059, u'sortableName': u'Duck, Huey', u'surname': u'Duck', u'year': None }, ] }, } """

        staff_data = self.get(
            'staff/{gradebookId}'.format(
                gradebookId=gradebook_id or self.gradebook_id
            ),
            params=None,
        )
        if simple:
            simple_list = []
            unraveled_list = self.unravel_staff(staff_data)
            for member in unraveled_list.__iter__():
                simple_list.append({
                    'accountEmail': member['accountEmail'],
                    'displayName': member['displayName'],
                    'role': member['role'],
                })
            return simple_list
        return staff_data['data']