Pry "next" alias does not work

[mdeguzis]

~/.pryrc

# Hit Enter to repeat last command
Pry::Commands.command /^$/, "repeat last command" do
  pry_instance.run_command Pry.history.to_a.last
end

Error:

[1] pry(#<Core::Pkg::Name>)>
NameError: undefined local variable or method `pry_instance' for #<#<Class:0x00007f37842bafa8>:0x00007f3783e8a7d0>
from /local/home/deguzim/.pryrc:10:in `block in __pry__'