input: def generateMarkov(text: str) -> str:
      """Generate a Markov chain from the given text and produce a randomly generated text sequence using the Markov chain.
      >>> generateMarkov('Alice was beginning to get very tired of sitting by her sister on the bank, and of having nothing to do: once or twice she had peeped into the book her sister was reading, but it had no pictures or conversations in it, `and what is the use of a book,' thought Alice `without pictures or conversation?')
      "sitting by her sister on the bank, and of having nothing to do: once or twice she had peeped into the book her sister was reading, but it had no pictures or conversations in it, `and what is the use of a book,' thought Alice `without pictures or conversation?' thought Alice `without pictures or conversation?' thought Alice `without pictures or conversation?'"
      """
output:     
      import random
      from collections import defaultdict
  
      words = text.split()
      markov_chain = defaultdict(list)
  
      for i in range(len(words) - 1):
          markov_chain[words[i]].append(words[i + 1])
  
      start_word = random.choice(words)
      generated_text = [start_word]
  
      for _ in range(len(words) - 1):
          next_word = random.choice(markov_chain[generated_text[-1]])
          generated_text.append(next_word)
          if next_word == generated_text[0]:
              break
  
      return ' '.join(generated_text)
  