code: func NewDNSProviderConfig(config *Config) (*DNSProvider, error) {
  	if config == nil {
  		return nil, errors.New("bindman: the configuration of the DNS provider is nil")
  	}
  
  	if config.BaseURL == "" {
  		return nil, fmt.Errorf("bindman: bindman manager address missing")
  	}
  
  	bClient, err := client.New(config.BaseURL, config.HTTPClient)
  	if err != nil {
  		return nil, fmt.Errorf("bindman: %v", err)
  	}
  
  	return &DNSProvider{config: config, client: bClient}, nil
  }
docs: // NewDNSProviderConfig return a DNSProvider instance configured for Bindman.