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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(self):
 """List all accounts"""

        _, accounts = BaseAccount.search()

        if ROLE_ADMIN not in session['user'].roles:
            accounts = list(filter(lambda acct: acct.account_id in session['accounts'], accounts))

        if accounts:
            return self.make_response({
                'message': None,
                'accounts': [x.to_json(is_admin=ROLE_ADMIN in session['user'].roles or False) for x in accounts]
            })
        else:
            return self.make_response({
                'message': 'Unable to find any accounts',
                'accounts': None
            }, HTTP.NOT_FOUND)