text: import math
  user_name = input("What is your name? ")
  
  # Concatenation:
  greeting = "Hello, " + user_name + "!"
  
  # The format() method:
  greeting = "Hello, {}!".format(user_name)
  
  # f-string:
  greeting = f"Hello, {user_name}!"
  print(greeting)
  
  # format specification is also available:
  pi_statement = f"pi is {math.pi:.4f}"
  print(pi_statement)