on the right of the operatorprovide the object (or objectsembedded in tuplethat you want python to insert into the format string on the left in place of the conversion target (or targetsfor instancein the formatting example we saw earlier in this the integer replaces the % in the format string on the leftand the string 'deadreplaces the % the result is new string that reflects these two substitutionswhich may be printed or saved for use in other roles'that is % % bird!( 'dead'that is dead birdformat expression technically speakingstring formatting expressions are usually optional--you can generally do similar work with multiple concatenations and conversions howeverformatting allows us to combine many steps into single operation it' powerful enough to warrant few more examplesexclamation 'ni'the knights who say % !exclamation 'the knights who say ni!string substitution '% % % you( 'spam' ' spam youtype-specific substitutions '% -% -% ( [ ]' - -[ ]all types match % target the first example here plugs the string 'niinto the target on the leftreplacing the % marker in the second examplethree values are inserted into the target string note that when you're inserting more than one valueyou need to group the values on the right in parentheses ( put them in tuplethe formatting expression operator expects either single item or tuple of one or more items on its right side the third example again inserts three values--an integera floating-point objectand list object--but notice that all of the targets on the left are %swhich stands for conversion to string as every type of object can be converted to string (the one used when printing)every object type works with the % conversion code because of thisunless you will be doing some special formatting% is often the only code you need to remember for the formatting expression againkeep in mind that formatting always makes new stringrather than changing the string on the leftbecause strings are immutableit must work this way as beforeassign the result to variable name if you need to retain it advanced formatting expression syntax for more advanced type-specific formattingyou can use any of the conversion type codes listed in table - in formatting expressionsthey appear after the character in substitution targets programmers will recognize most of these because python string formatting supports all the usual printf format codes (but returns the resultinstead string fundamentals