how to get index of a letter in string python code example

Example 1: python index of string

string = "Hello World"
string_slice = string[1:10] # "ello Worl" (index 1 up to 10)
string_last_chars = string[-5:] # "World" (5th index from last to the end)
H = string[0] # "H"

Example 2: how to find the indexes of a substring in a string in python

import re
# matches_position_start will be a list of starting index positions
matches_start = re.finditer(word.lower(), string.lower())
matches_position_start = [match.start() for match in matches_start]

# matches_position_end will be a list of ending index positions
matches_end = re.finditer(word.lower(), string.lower())
matches_position_end = [match.end() for match in matches_end]