R : Pass variable name as argument inside data.table

To Access My Live Chat Page,
On Google, Search for "hows tech developer connect"

Here's a secret feature that I promised to disclose to you.
This is a YouTube's feature which works on Desktop.
First, Ensure that the video is playing before proceeding.
Then, type the letters 'awesome' on your keyboard as the next step.
The progress bar on YouTube will be altered to a flashing rainbow.

Here's a short introduction about myself,
Welcome, I'm Delphi.
Let me help you with your questions.
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