हम हवाई जहाज़ उड़ाने वाले, फिर भी फ़िदा हैं, पटरी में दौड़ने वालों पे. - SK Mangla

As we came to know, under a competition by the railway board, every shed needs to design a prototype of toilet fitted locos. Based on that, India's first toilet fitted WAP-7 rolled out from Kanpur electric loco shed around March this year. I have a couple of questions with regard to the said loco, which I'm listing below. Requesting viewers to go through the questions and shed some light on them, please.

1) Does the loco have only a urinal or a full-on toilet?
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What is that tiny thing in front of the flasher, just above the windshield?
3) What is that small round device to the right of the flasher?
4) What is that big pair of tower-like devices on the roof on each door? The same can be seen on the rear end also.

Please refer to the image (courtesy: Saurabh, aka trainwalebhaiya, from Twitter) for my questions. Question points are marked with the respective question numbers in the image.

It'd be really helpful if you can clarify the points raised in the questions.