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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_logins(self, user_id, start_date=None):
 """Gets the login history for a user, default start_date is 30 days ago :param int id: User id to get :param string start_date: "%m/%d/%Y %H:%M:%s" formatted string. :returns: list https://softlayer.github.io/reference/datatypes/SoftLayer_User_Customer_Access_Authentication/ Example:: get_logins(123, '04/08/2018 0:0:0') """


        if start_date is None:
            date_object = datetime.datetime.today() - datetime.timedelta(days=30)
            start_date = date_object.strftime("%m/%d/%Y 0:0:0")

        date_filter = {
            'loginAttempts': {
                'createDate': {
                    'operation': 'greaterThanDate',
                    'options': [{'name': 'date', 'value': [start_date]}]
                }
            }
        }
        login_log = self.user_service.getLoginAttempts(id=user_id, filter=date_filter)
        return login_log