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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_sorted_action_keys(self, keys_list):
 """ This function returns only the elements starting with 'action-' in 'keys_list'. The returned list is sorted by the index appended to the end of each element """

        # The names can be found in reflexrulewidget.pt inside the
        # Reflex action rules list section.
        action_list = []
        for key in keys_list:
            if key.startswith('action-'):
                action_list.append(key)
        action_list.sort()
        return action_list