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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_configured_rc_input_names(self, channel):
 """ find all RC mappings to a given channel and return their names :param channel: input channel (0=first) :return: list of strings or None """

        ret_val = []
        for key in self._ulog.initial_parameters:
            param_val = self._ulog.initial_parameters[key]
            if key.startswith('RC_MAP_') and param_val == channel + 1:
                ret_val.append(key[7:].capitalize())

        if len(ret_val) > 0:
            return ret_val
        return None