Remap eject key to backslash There is an eject key on the upper right corner of my Magic Keyboard. Since I'm neither using the eject key directly nor any of the shortcuts associated to it, I would like to remap it to a symbol that I use more often. That is in my case the backslash. 

How can I remap the eject key to backslash, preferably without using third-party software? I'm using High Sierra version 10.13.3 on a Macbook Pro 2017.
Scripting Key Remapping

Keys can be remapped via the command-line tool hidutil. For example, use the hidutil command-line tool to remap the 'A' key to the 'B' key as shown in Listing 1. The map array consists of two key/value pairs that contain the source (HIDKeyboardModifierMappingSrc) and destination (HIDKeyboardModifierMappingDstKey) of the key remapping. The keys take a hexadecimal value that consists of 0x700000000 or’d with the desired keyboard usage value (see Table 1 for usage values).

Listing 1:   Remapping keys in a script Use The value From the Table Given In the Link

$ hidutil property --set '{"UserKeyMapping":[{"HIDKeyboardModifierMappingSrc":0x700000004,"HIDKeyboardModifierMappingDst":0x700000005},{"HIDKeyboardModifierMappingSrc":0x700000005,"HIDKeyboardModifierMappingDst":0x700000004}]}'
)


A null result indicates that there are no key remappings active.

Listing 2:  Checking Key Remapping state

$ hidutil property --get "UserKeyMapping"
(null)



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