Printing tuple with string formatting in Python

Question

>>> thetuple = (1, 2, 3)
>>> print "this is a tuple: %s" % (thetuple,)
this is a tuple: (1, 2, 3)

Making a singleton tuple with the tuple of interest as the only item, i.e. the (thetuple,) part, is the key bit here.

Note that the % syntax is obsolete. Use str.format, which is simpler and more readable:

t = 1,2,3
print 'This is a tuple {0}'.format(t)

Many answers given above were correct. The right way to do it is:

>>> thetuple = (1, 2, 3)
>>> print "this is a tuple: %s" % (thetuple,)
this is a tuple: (1, 2, 3)

However, there was a dispute over if the '%' String operator is obsolete. As many have pointed out, it is definitely not obsolete, as the '%' String operator is easier to combine a String statement with a list data.

Example:

>>> tup = (1,2,3)
>>> print "First: %d, Second: %d, Third: %d" % tup
First: 1, Second: 2, Third: 3

However, using the .format() function, you will end up with a verbose statement.

Example:

>>> tup = (1,2,3)
>>> print "First: %d, Second: %d, Third: %d" % tup
>>> print 'First: {}, Second: {}, Third: {}'.format(1,2,3)
>>> print 'First: {0[0]}, Second: {0[1]}, Third: {0[2]}'.format(tup)

First: 1, Second: 2, Third: 3
First: 1, Second: 2, Third: 3
First: 1, Second: 2, Third: 3

Further more, '%' string operator also useful for us to validate the data type such as %s, %d, %i, while .format() only support two conversion flags: '!s' and '!r'.

>>> tup = (1, 2, 3)
>>> print "Here it is: %s" % (tup,)
Here it is: (1, 2, 3)
>>>

Note that (tup,) is a tuple containing a tuple. The outer tuple is the argument to the % operator. The inner tuple is its content, which is actually printed.

(tup) is an expression in brackets, which when evaluated results in tup.

(tup,) with the trailing comma is a tuple, which contains tup as is only member.