Ender 5 fan duct

A fan duct for Creality Ender 5. It supports single or dual 5015 fans. I've used it for a while and it works fine. It's fairly easy to print and assemble. Should you break any part, it's quick to print again. It's not screwed on the backplate, it only hangs on the side brackets, but it sits firmly in place nonetheless. This is very much a work in progress, so please consider that if you print it.

Design rationale:

* Fairly strong
* Fairly light
* Fairly easy to print
* Minimize air from hot-end fan on part
* Easy to remix/modify
* Easy to install
* Good part cooling

Instructions:
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Materials:
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* 4 x M3 screws for the hot-end fan. The original hot-end fan screws will do.
* 4 x M2 screws for the cable holder and lifters. The original part cooling fan screws will do.
* 2 x M3x20mm screws. These are for securing the 5015 fans.

Prints:
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I highly suggest using PETG as some parts will require some force to assemble. PLA might work, but