code: public function setMethod($method)
  	{
  		$method = strtolower($method);
  
  		if (!array_key_exists($method, $this->curl->getAllowedMethods())) {
  			throw new \InvalidArgumentException("Method [$method] not a valid HTTP method.");
  		}
  
  		$this->method = $method;
  
  		return $this;
  	}
docs: Set the HTTP method of the request.
  
  @param string $method