code: private function checkDefaults($options)
  	{
  		if(!isset($options['request_option']))
  		{
  			$options['request_option'] = 'Shop';
  		}
  		if(!isset($options['from_country']))
  		{
  			$options['from_country'] = 'US';
  		}
  		if(!isset($options['to_country']))
  		{
  			$options['to_country'] = 'US';
  		}
  		if(!isset($options['service_type']))
  		{
  			$options['service_type'] = '03';
  		}
  		if(!isset($options['from_state']))
  		{
  			$options['from_state'] = '';
  		}
  		if(!isset($options['to_state']))
  		{
  			$options['to_state'] = '';
  		}
  
  		$this->commercial_rates = (isset($options['commercial']) && $options['commercial']) ? true : false;
  
  		$this->negotiated_rates = (isset($options['negotiated_rates']) && $options['negotiated_rates']) ? true : false;
  			
  		return $options;
  	}
docs: Make sure the options array contains all
  of the required fields.  If not, populate
  them with the default values.
  
  @param options array
  
  @return array