input: from collections import Counter
  
  
  def generate_ngrams(text: str, window_size: int) -> Counter:
      """ Given a string of text and a window size, generate the n-grams of the text with the specified window size.
      Returns a Counter object containing the n-grams and their frequencies.
      >>> text = "The quick brown fox jumps over the lazy dog"
      >>> window_size = 3
      >>> generate_ngrams(text, window_size)
      Counter({'the quick brown': 3, 'quick brown fox': 2, 'over the lazy': 1, 'brown fox jumps': 1, 'fox jumps over': 1, 'the lazy dog': 1, 'jumps over the': 1, 'quick brown fox jumps': 1})
      """
output:     ngrams = [text[i:i+window_size] for i in range(len(text) - window_size + 1)]
      return Counter(ngrams)