LogFAQs > #923844081

I've never actually farmed in BL2. Always made due with doing all sidequests before moving on with the plot.
Little tip: Since you're Lvl 20, try the seasonal Headhunter DLCs. They're all at your level and drop some insanely powerful weapons. I didn't need to switch unti Lvl 30.
Also use the Shift codes to get Golden Keys for that chest in Sanctuary, always grants purple gear

https://borderlands.fandom.com/wiki/Add-on_content

The ones listed as Headhunter are the ones you want

http://orcz.com/borderlands_2:_Golden_Key

Enter the non expired codes at the BL2 main menu, there should be an option to do so
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