input: Write a python function to tokenize a given text into sentences and words using NLTK library.
  assert tokenize_text("Hello! How are you? I am fine.") == (['Hello!', 'How are you?', 'I am fine.'], ['Hello', '!', 'How', 'are', 'you', '?', 'I', 'am', 'fine', '.'])
  assert tokenize_text("This is a test. Testing sentence tokenization.") == (['This is a test.', 'Testing sentence tokenization.'], ['This', 'is', 'a', 'test', '.', 'Testing', 'sentence', 'tokenization', '.'])
output: def tokenize_text(text):
      import nltk
      from nltk.tokenize import sent_tokenize, word_tokenize
      nltk.download('punkt')
      
      sentences = sent_tokenize(text)
      words = word_tokenize(text)
      
      return sentences, words