get_signalcheck -  perform a signal check.

        Parameters
        ----------
        sar : dict
            signal-api-request specified as a dictionary of parameters.
            All of these parameters are optional. For details
            check https://api.postcode.nl/documentation/signal-api-example.

        returns :
            a response dictionary

def get_signalcheck(self, sar, **params):
        """get_signalcheck -  perform a signal check.

        Parameters
        ----------
        sar : dict
            signal-api-request specified as a dictionary of parameters.
            All of these parameters are optional. For details
            check https://api.postcode.nl/documentation/signal-api-example.

        returns :
            a response dictionary
        """
        params = sar
        endpoint = 'rest/signal/check'

        # The 'sar'-request dictionary should be sent as valid JSON data, so
        # we need to convert it to JSON
        # when we construct the request in API.request
        retValue = self._API__request(endpoint, 'POST',
                                      params=params, convJSON=True)

        return retValue