text: '''A program to extract the values of a particular key from nested dictionary'''
  
  D = {
      "D1": {"1": 4, "a": 67, "2": "dictionary0", "b": 864, "3": "Lists"},
      "D2": {"1": 547, "a": "hello", "2": 57895, "b": 2464, "3": "World"},
      "D3": {"1": "Python", "a": 54.234, "2": "Java", "b": "C++", "3": "Ruby"}
  }
  print("\nThe nested Dictionary is:\n", str(D))
  ele = input("\nEnter the key whos values are to be extracted:\n")
  
  # loop to find the values of key
  r = [sub[ele] for sub in D.values() if ele in sub.keys()]
  
  # to print the extracted values of key
  print("\nThe values of {} are : {}".format(ele, r))
  