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Emacs, 47 bytes
abcdefghijklmnopqrstuvwxyz^M
^P
<F3>
^K ^K ^Y ^Y
^P
^<space> ^F ^W ^E ^Y ^A
<F4>
^U 2 4 F4
Where ^P means "Control P", etc. That's 47 bytes, since the F3 and F4 keys require two ASCII bytes.
After entering the starting input, it defines a keyboard macro to duplicate the line ...