How to make a python program that lists the positions and displays and error message if not found

Your code is having multiple errors. I am pasting here the sample code for your reference:

from collections import defaultdict

sentence_string = raw_input('Enter Sentence: ')
# Enter Sentence: Here is the content I need to check for index of all words as Yes Hello Yes Yes Hello Yes

word_string = raw_input("Enter Words: ")
# Enter Words: yes hello

word_list = sentence_string.lower().split()
words = word_string.lower().split()

my_dict = defaultdict(list)
for i, word in enumerate(word_list):
     my_dict[word].append(i)

for word in words:
    print "The word" , word, "is in position " , my_dict[word]

# The word yes is in position  [21, 23, 24, 26]
# The word hello is in position  [22, 25]

The approach here is:

1. Break your sentence i.e sentence_string here into list of words
2. Break your word string into list of words.
3. Create a dictionary my_dict to store all the indexes of the words in word_list
4. Iterate over the words to get your result with index, based on the value you store in my_dict.

Note: The commented part in above example is basically the output of the code.