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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 rpc_get_account_tokens(self, address, **con_info):
 """ Get the types of tokens that an account owns Returns the list on success """

        if not check_account_address(address):
            return {'error': 'Invalid address', 'http_status': 400}

        # must be b58
        if is_c32_address(address):
            address = c32ToB58(address)

        db = get_db_state(self.working_dir)
        token_list = db.get_account_tokens(address)
        db.close()
        return self.success_response({'token_types': token_list})