src/RequestOptions/RequestOptions.php
public function addDefaultHeaders($headers)
    {
        foreach ($headers as $name => $value) {
            $this->addDefaultHeader($name, $value);
        }

        return $this;
    }
public function addDefaultHeaders($headers)
    {
        foreach ($headers as $name => $value) {
            $this->addDefaultHeader($name, $value);
        }

        return $this;
    }
public function addDefaultHeaders ( $ headers ) { foreach ( $ headers as $ name => $ value ) { $ this -> addDefaultHeader ( $ name , $ value ) ; } return $ this ; }
Add the headers passed if the value isn't already set.

@param array $headers List of header name/value pairs

@return $this
Add the headers passed if the value isn t already set .