old_contents: import numpy as np
  
  from moviepy import *
  from moviepy.video.tools.segmenting import find_objects
  
  
  # WE CREATE THE TEXT THAT IS GOING TO MOVE, WE CENTER IT.
  
  screensize = (720, 460)
  txtClip = TextClip(
      "Cool effect", color="white", font="Amiri-Bold", kerning=5, font_size=100
  )
  cvc = CompositeVideoClip([txtClip.with_position("center")], size=screensize)
  
  # THE NEXT FOUR FUNCTIONS DEFINE FOUR WAYS OF MOVING THE LETTERS
  
  
  # helper function
  rotMatrix = lambda a: np.array([[np.cos(a), np.sin(a)], [-np.sin(a), np.cos(a)]])
  
  
  def vortex(screenpos, i, nletters):  # noqa D103
      d = lambda t: 1.0 / (0.3 + t**8)  # damping
      a = i * np.pi / nletters  # angle of the movement
      v = rotMatrix(a).dot([-1, 0])
      if i % 2:
          v[1] = -v[1]
      return lambda t: screenpos + 400 * d(t) * rotMatrix(0.5 * d(t) * a).dot(v)
  
  
  def cascade(screenpos, i, nletters):  # noqa D103
      v = np.array([0, -1])
      d = lambda t: 1 if t < 0 else abs(np.sinc(t) / (1 + t**4))
      return lambda t: screenpos + v * 400 * d(t - 0.15 * i)
  
  
  def arrive(screenpos, i, nletters):  # noqa D103
      v = np.array([-1, 0])
      d = lambda t: max(0, 3 - 3 * t)
      return lambda t: screenpos - 400 * v * d(t - 0.2 * i)
  
  
  def vortexout(screenpos, i, nletters):  # noqa D103
      d = lambda t: max(0, t)  # damping
      a = i * np.pi / nletters  # angle of the movement
      v = rotMatrix(a).dot([-1, 0])
      if i % 2:
          v[1] = -v[1]
      return lambda t: screenpos + 400 * d(t - 0.1 * i) * rotMatrix(-0.2 * d(t) * a).dot(
          v
      )
  
  
  # WE USE THE PLUGIN find_objects TO LOCATE AND SEPARATE EACH LETTER
  
  letters = find_objects(cvc)  # a list of ImageClips
  
  
  # WE ANIMATE THE LETTERS
  
  
  def moveLetters(letters, funcpos):  # noqa D103
      return [
          letter.set_pos(funcpos(letter.screenpos, i, len(letters)))
          for i, letter in enumerate(letters)
      ]
  
  
  clips = [
      CompositeVideoClip(moveLetters(letters, funcpos), size=screensize).subclip(0, 5)
      for funcpos in [vortex, cascade, arrive, vortexout]
  ]
  
  # WE CONCATENATE EVERYTHING AND WRITE TO A FILE
  
  final_clip = concatenate_videoclips(clips)
  final_clip.write_videofile("../../coolTextEffects.avi", fps=25, codec="mpeg4")
  
new_contents: import numpy as np
  
  from moviepy import *
  from moviepy.video.tools.segmenting import find_objects
  
  
  # WE CREATE THE TEXT THAT IS GOING TO MOVE, WE CENTER IT.
  
  screensize = (720, 460)
  txtClip = TextClip(
      "Cool effect", color="white", font="Amiri-Bold", kerning=5, font_size=100
  )
  cvc = CompositeVideoClip([txtClip.with_position("center")], size=screensize)
  
  # THE NEXT FOUR FUNCTIONS DEFINE FOUR WAYS OF MOVING THE LETTERS
  
  
  # helper function
  rotMatrix = lambda a: np.array([[np.cos(a), np.sin(a)], [-np.sin(a), np.cos(a)]])
  
  
  def vortex(screenpos, i, nletters):  # noqa D103
      d = lambda t: 1.0 / (0.3 + t**8)  # damping
      a = i * np.pi / nletters  # angle of the movement
      v = rotMatrix(a).dot([-1, 0])
      if i % 2:
          v[1] = -v[1]
      return lambda t: screenpos + 400 * d(t) * rotMatrix(0.5 * d(t) * a).dot(v)
  
  
  def cascade(screenpos, i, nletters):  # noqa D103
      v = np.array([0, -1])
      d = lambda t: 1 if t < 0 else abs(np.sinc(t) / (1 + t**4))
      return lambda t: screenpos + v * 400 * d(t - 0.15 * i)
  
  
  def arrive(screenpos, i, nletters):  # noqa D103
      v = np.array([-1, 0])
      d = lambda t: max(0, 3 - 3 * t)
      return lambda t: screenpos - 400 * v * d(t - 0.2 * i)
  
  
  def vortexout(screenpos, i, nletters):  # noqa D103
      d = lambda t: max(0, t)  # damping
      a = i * np.pi / nletters  # angle of the movement
      v = rotMatrix(a).dot([-1, 0])
      if i % 2:
          v[1] = -v[1]
      return lambda t: screenpos + 400 * d(t - 0.1 * i) * rotMatrix(-0.2 * d(t) * a).dot(
          v
      )
  
  
  # WE USE THE PLUGIN find_objects TO LOCATE AND SEPARATE EACH LETTER
  
  letters = find_objects(cvc)  # a list of ImageClips
  
  
  # WE ANIMATE THE LETTERS
  
  
  def moveLetters(letters, funcpos):  # noqa D103
      return [
          letter.with_position(funcpos(letter.screenpos, i, len(letters)))
          for i, letter in enumerate(letters)
      ]
  
  
  clips = [
      CompositeVideoClip(moveLetters(letters, funcpos), size=screensize).subclip(0, 5)
      for funcpos in [vortex, cascade, arrive, vortexout]
  ]
  
  # WE CONCATENATE EVERYTHING AND WRITE TO A FILE
  
  final_clip = concatenate_videoclips(clips)
  final_clip.write_videofile("../../coolTextEffects.avi", fps=25, codec="mpeg4")
  
subject: change 'set_pos' to 'with_position' (#1836)