code: def test_transformations():
      # Meta-c (capitalize-word)
      result, cli = _feed_cli_with_input("hello world\01\x1bc\n")
      assert result.text == "Hello world"
      assert result.cursor_position == len("Hello")
  
      # Meta-u (uppercase-word)
      result, cli = _feed_cli_with_input("hello world\01\x1bu\n")
      assert result.text == "HELLO world"
      assert result.cursor_position == len("Hello")
  
      # Meta-u (downcase-word)
      result, cli = _feed_cli_with_input("HELLO WORLD\01\x1bl\n")
      assert result.text == "hello WORLD"
      assert result.cursor_position == len("Hello")
  
      # ControlT (transpose-chars)
      result, cli = _feed_cli_with_input("hello\x14\n")
      assert result.text == "helol"
      assert result.cursor_position == len("hello")
  
      # Left, Left, Control-T (transpose-chars)
      result, cli = _feed_cli_with_input("abcde\x1b[D\x1b[D\x14\n")
      assert result.text == "abdce"
      assert result.cursor_position == len("abcd")
  
imports: from __future__ import unicode_literals
  from prompt_toolkit.application import Application
  from prompt_toolkit.buffer import Buffer, AcceptAction
  from prompt_toolkit.clipboard import InMemoryClipboard, ClipboardData
  from prompt_toolkit.enums import DEFAULT_BUFFER, EditingMode
  from prompt_toolkit.eventloop.posix import PosixEventLoop
  from prompt_toolkit.history import InMemoryHistory
  from prompt_toolkit.input import PipeInput
  from prompt_toolkit.interface import CommandLineInterface
  from prompt_toolkit.key_binding.manager import KeyBindingManager
  from prompt_toolkit.output import DummyOutput
  from prompt_toolkit.terminal.vt100_input import ANSI_SEQUENCES
  from functools import partial
  import pytest
label_desc: Use image node_id 7 for calling a global function with example usage: test_transformations() without return types