code: def suspend_to_bg(event):
      event.cli.suspend_to_background()
  
imports: import signal
  import sys
  from prompt_toolkit.enums import DEFAULT_BUFFER, SEARCH_BUFFER
  from prompt_toolkit.filters import HasFocus, HasSelection, Condition, ViInsertMode, EmacsInsertMode, HasCompletions
  from prompt_toolkit.filters.cli import ViMode
  from prompt_toolkit.keys import Keys
  from prompt_toolkit.key_binding.bindings.completion import display_completions_like_readline
  from IPython.utils.decorators import undoc
label_desc: Use image node_id 9 for calling a global function with example usage: suspend_to_bg(event) without return types