As a more advanced extension, string formatting also allows conversion targets on the left to refer to the keys in a dictionary coded on the right and fetch the corresponding values.

Age.py

>>> # Template with substitution targets
>>> reply = """
Greetings...
Hello %(name)s!
Your age is %(age)s
"""
>>> values = {'name': 'Bob', 'age': 40} # Build up values to substitute
>>> print(reply % values) # Perform substitutions