def  my_find1(word, character_to_search_for):
    letter_found = []
    word = word.lower()
    character_to_search_for = character_to_search_for.lower()
    for count in range(len(word)):
      if word[count] == character_to_search_for:
        letter_found.append(count)
    return letter_found
print(my_find1("banana", "a"))