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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_config(self, retrieve="all"):
 """get_config implementation for FortiOS."""

        get_startup = retrieve == "all" or retrieve == "startup"
        get_running = retrieve == "all" or retrieve == "running"
        get_candidate = retrieve == "all" or retrieve == "candidate"

        if retrieve == "all" or get_running:
            result = self._execute_command_with_vdom('show')
            text_result = '\n'.join(result)

            return {
                'startup': u"",
                'running': py23_compat.text_type(text_result),
                'candidate': u"",
            }

        elif get_startup or get_candidate:
            return {
                'startup': u"",
                'running': u"",
                'candidate': u"",
            }