How do I add a newline to hs.eventtap.keyStrokes in Hammerspoon?

I just started using Hammerspoon. I'm trying to output multiple lines of text by pressing Cmd+Shift+l .

Here is what I have tried so far :

hs.hotkey.bind({"cmd", "shift"}, "l", function()
  hs.eventtap.keyStrokes('from sklearn import metrics')
  hs.eventtap.keyStroke("return")
  hs.eventtap.keyStrokes('from sklearn.cross_validation import train_test_split')
end)

I also tried with inline "\n" and "%\n"

How can I bind a key combination to output multiple lines of text? Or, How can I send a newline character?

I ran into the same problem. I tried what you tried above and although it worked in many applications, it still didn't work in Chrome. I used the pasteboard (clipboard) as a workaround.

jira_text = [[a 
long 
multi-line
string]]

-- Hotkey JIRA text
hs.hotkey.bind({"cmd", "alt", "ctrl"}, "J", function ()
  hs.alert.show("Remove this message after debugging!")
  --hs.eventtap.keyStrokes(jira_text)#don't do this!
  hs.pasteboard.writeObjects(jira_text)
  hs.eventtap.keyStroke("cmd", "v")
  end)
--

You could improve it further by using a custom named pasteboard so it doesn't overwrite your clipboard contents (if you want that).