Script to study about string indexes and substrings.

substrings.py

def set_line(word_length):
    line = '+'
    line += word_length * '---+'
    line += '\n'

    return line

def set_letters(word):
    count = 1
    letters = '' 

    for letter in word:
        letters += '| {} '.format(letter)

        if (count == len(word)):
            letters += '|\n'
        
        count += 1
    
    return letters

def set_indexes(word, positive = True):
    indexes = ''
    count = 0 if positive else -len(word)
    limit = len(word)-1 if positive else -1

    for letter in word:
        if positive:
            index = '*' if count > 9 else count
        else:
            index = '* ' if count < -9 else count

        space = '   ' if positive else '  '

        indexes += '{}{}'.format(index, space)

        if (count == limit):
            final_index = count+1 if positive else ''
            indexes += '{}\n'.format(final_index)

        count += 1
    
    return indexes

print('\nS U B S T R I N G S  E M  P Y T H O N :)\n\n')
word = str(input('Digite uma string:  '))

substring_graphic = '\n' + set_line(len(word))
substring_graphic += set_letters(word)
substring_graphic += set_line(len(word))
substring_graphic += set_indexes(word)
substring_graphic += set_indexes(word, False)
print(substring_graphic)

incluido = int(input('Incluído:  '))
excluido = int(input('Excluído:  '))

print(word[incluido:excluido])