import string
import math
import re

# All the lowercase ASCII letters: 'abcdefghijklmnopqrstuvwxyz'
print(string.ascii_lowercase) 

# The mathematical constants pi and e, both floating-point numbers
print(math.pi) # ratio of circumference of a circle to its diameter
print(math.e) # natural base of logarithms


# This integer is an option which we can pass to functions in the re
# (regular expression) library.
print(re.IGNORECASE)