Python IDLE theme inspired by Atom's One Dark

config-highlight.def

[One Dark]
normal-foreground = #ffffff
normal-background = #282c34
keyword-foreground = #c678dd
keyword-background = #282c34
builtin-foreground = #56b6c2
builtin-background = #282c34
comment-foreground = #5c6370
comment-background = #282c34
string-foreground = #98c379
string-background = #282c34
definition-foreground = #61afef
definition-background = #282c34
hilite-foreground = #ffffff
hilite-background = #3a3f4b
break-foreground = #FFFFFF
break-background = #808000
hit-foreground = #ffffff
hit-background = #324365
error-foreground = #FFFFFF
error-background = #5c3939
context-foreground = #ffffff
context-background = #21252b
linenumber-foreground = #636d83
linenumber-background = #282c34
cursor-foreground = #ffffff
stdout-foreground = #d19a66
stdout-background = #282c34
stderr-foreground = #ff6347
stderr-background = #282c34
console-foreground = #e06c75
console-background = #282c34

Installation:

1. Ensure IDLE is closed
2. Open your .idlerc file, usually in your home directory
3. Paste in the settings and save
4. Open IDLE, Options -> Configure IDLE
5. Under the Highlights tab, One Dark should now be a custom theme available in the drop-down list