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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_candidate_config(self, merge=False, formal=False):
 """ Retrieve the configuration loaded as candidate config in your configuration session. :param merge: Merge candidate config with running config to return the complete configuration including all changed :param formal: Return configuration in IOS-XR formal config format """

        command = "show configuration"
        if merge:
            command += " merge"
        if formal:
            command += " formal"
        response = self._execute_config_show(command)

        match = re.search(".*(!! IOS XR Configuration.*)$", response, re.DOTALL)
        if match is not None:
            response = match.group(1)

        return response