redefined-outer-name:7::Redefining name 'i' from outer scope (line 6)
redefined-outer-name:12::Redefining name 'i' from outer scope (line 11)
redefined-outer-name:17::Redefining name 'i' from outer scope (line 16)
redefined-outer-name:22::Redefining name 'a' from outer scope (line 21)