ModuleNotFoundError: No module named 'TTS'

Code raises error when trying to follow the official snippets.

/Users/sarit/.pyenv/versions/learn_typhoon_ocr/bin/python /Users/sarit/fullstack/learn_typhoon_ocr/test_pythaitts.py 
Traceback (most recent call last):
  File "/Users/sarit/fullstack/learn_typhoon_ocr/test_pythaitts.py", line 34, in <module>
    tts = TTS(pretrained="khanomtan")
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/sarit/.pyenv/versions/learn_typhoon_ocr/lib/python3.12/site-packages/pythaitts/__init__.py", line 40, in __init__
    self.load_pretrained(version=version)
  File "/Users/sarit/.pyenv/versions/learn_typhoon_ocr/lib/python3.12/site-packages/pythaitts/__init__.py", line 50, in load_pretrained
    from pythaitts.pretrained.khanomtan_tts import KhanomTan
  File "/Users/sarit/.pyenv/versions/learn_typhoon_ocr/lib/python3.12/site-packages/pythaitts/pretrained/khanomtan_tts.py", line 12, in <module>
    from TTS.utils.synthesizer import Synthesizer
ModuleNotFoundError: No module named 'TTS'

Process finished with exit code 1

import sounddevice as sd
import soundfile as sf
from pythaitts import TTS

tts = TTS()

tts = TTS(pretrained="khanomtan")
file = tts.tts("ภาษาไทย", speaker_idx="Linda", filename="kanontan.wav")
data, samplerate = sf.read(file)
print(f"เล่นจากไฟล์: {file}")
sd.play(data, samplerate)
sd.wait()  # รอจนเล่นเสร็จ

pythaitts==0.4.2