Sieb fluid system tube- fell off today???

[Yoadrian]

I was trying to find the drain holes under the top today and I also checked the oil level. The dipstick was tough to get back in, but it finally went.

Just moved the car and found a small tube, 1/4 inch in diameter, about 6 inches long on the ground under where the car was.

Any idea what this tube may be for and if I am safe to drive without it in place for a while?

Thanks.