Python Programming with the Java™ Class Libraries: A Tutorial for Building Web and Enterprise Applications with Jython

Formatting Strings—Modulus

Although not actually modulus, the Python % operator works similarly in string formatting to interpolate variables into a formatting string. If you've programmed in C, you'll notice that % is much like C's printf(), sprintf(), and fprintf() functions.

There are two forms of %, one of which works with strings and tuples, the other with dictionaries.

StringOperand % TupleOperand

StringOperand % DictionaryOperand

Both return a new formatted string quickly and easily.

% Tuple String Formatting

In the StringOperand % TupleOperand form, StringOperand represents special directives within the string that help format the tuple. One such directive is %s, which sets up the format string

 >>> format = "%s is my friend and %s ...