public function setConfig($key = null, $value = null)
    {
        if ($key == null || $value == null) {
            return null;
        }
        return ($this->config[$key] = $value);
    }
public function setConfig($key = null, $value = null)
    {
        if ($key == null || $value == null) {
            return null;
        }
        return ($this->config[$key] = $value);
    }
public function setConfig ( $ key = null , $ value = null ) { if ( $ key == null || $ value == null ) { return null ; } return ( $ this -> config [ $ key ] = $ value ) ; }
Set an API configuration key.

@param key $key The configuration key.
@param value $value The configuration key value.

@return boolean|null Result of the set.
Set an API configuration key .